


Dangerous Things

by rallamajoop



Series: Demoniality [1]
Category: Teen Wolf (TV)
Genre: Alternate Universe - Medieval, Alternate Universe - Werewolves Are Known, M/M, Magic!Stiles, Not-Actually-Evil-Demon!Derek, Soul-Bonding, Succubi & Incubi, dub-con/consent issues
Language: English
Status: Completed
Published: 2013-04-25
Updated: 2015-10-09
Packaged: 2017-12-09 11:04:21
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 18
Words: 143,768
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/773486
Author URL: https://archiveofourown.org/users/rallamajoop/pseuds/rallamajoop
Summary: <blockquote class="userstuff">
              <p>
  <i>"You want me to hold you down while we do this, Stiles?" says the incubus. In one sudden movement it has Stiles’ arm wrenched over his head and pinned it by the wrist below the headboard. "Would that make this easier for you?"</i>
</p><p>
  <i>Stiles swallows. "Maybe?" This whole thing where he gets the chance to opt out of having mindblowing sex with a demon of questionable intentions is causing him more unnecessary stress than he wants to deal with. Can't it just get on with ravishing him already?</i>
</p><p>
  <i>"You really think that’s what we do? You think we <b>need</b> to? Ever?" The incubus' breath ghosts warm against his neck. (Actually, Stiles has half an idea that ‘thinking’ isn’t much of good description of anything that’s gone through his head for a good few minutes. It’s so unfair of it to pick on him for that.)</i>
  <br/>
</p><hr/><p>AKA: The Medieval AU where Derek is an incubus and Stiles is so, <i>so</i> far out of his depth right now.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

  * For [velithya](https://archiveofourown.org/users/velithya/gifts).



> **Warnings/Content notes:** Contains several sex scenes of variously questionable consent (if generally less so as things progress), as well as some discussion (though no graphic depiction) of rape. Canon-typical levels of horror and violence also apply. 
> 
> There's also set to be a _lot_ of convoluted plot, and a large supporting cast - no-one in the character tags is here for a minor cameo. This is more or less how attempting to write a PWP always seems to go for me these days.
> 
> * * *
> 
>  **A note on side-stories:**  
>  The series attached to this fic features several short side-stories that fit in between scenes without being strictly crucial to the plot, including some from POV's other than Stiles'. For those who may feel like reading the whole thing in strictly chronological order, I'll link to them as they'd occur in the narrative. 
> 
> To begin with, there's a short prequel to the main story, [Three Beneath the Moon](http://archiveofourown.org/works/816932), covering some of what Stiles, Allison and Scott went through during Scott's earlier werewolf days in this universe, and Allison's relationship with the family business (though it's hardly essential reading and doesn't feature Derek as such, so if you'd rather skip straight to the juicier parts of the story, read on!)

By midday it's become pretty well inescapable that Lydia isn't waking up. 

Stiles has over a dozen different books open on the table in front of him, and the sum of what all of them together can tell him about incubi would hardly amount to a decent foreword. Only four of the books are properly his – dusty old things with no proper title-plate to give them away. Those are the ones Deaton entrusted to him, one a year on his birthday since Stiles' semi-official and frustratingly sporadic apprenticeship began in his fourteenth year. The rest he pilfered from the tower library (such as it is; a handful of bookshelves scattered through different rooms). His new collection comprises three histories, one genealogy of the Martin family, a bible, an old diary, an impressively bound tome written entirely in Latin, a Latin dictionary which has yet to allow Stiles to so much as _identify_ that first one – let alone get anything useful out of it – a blacksmithing manual, a book of poetry, a manual on swordsmanship meant for the knights in training, and two books on animal husbandry, and may lightning strike him down should Stiles ever claim those last few are anything but proof he's getting desperate. 

At fourteen, Stiles would probably have imagined that by the time he had _four whole books_ from Deaton he'd be ready to handle anything. In reality, his first book contains nothing but incredibly pedantic instructions on laboratory safety, and even the bestiary was evidently penned by someone who firmly believed that a little knowledge is a dangerous thing, considering how it dedicates page after page to graphic descriptions of exactly how screwed he is should he ever come face to face with any of these horrible monsters, but barely a single word to how one goes about killing them. Nothing. Nada. Naught.

The implication – which Stiles feels could stand to be a little more subtle, not that even Deaton actually _read_ his extended critical essay on the many flaws and omissions he'd found in that text when Stiles had presented it to him on his following visit – is that fourth-year apprentices like him are expected to deal with monsters by staying the hell out of the woods and leaving the hunting to the experts. Any other day, Stiles would be on right board with that without question. Today, Deaton's not here – his last visit was months ago. The hunters all rode out hunting days ago, Alison with them, and they're not due back for another two days at the earliest. Lord Martin rode out to the king's aid in the war on the eastern border with Stiles' dad and every knight in his employ around the same time as Deaton's last visit – further away than Stiles has ever been in his life. Even Harris is gone, having conveniently found a way to reinterpret the duties of stewardship in a manner that lets him spend most of the winter far away from here. 

Between the war and three long years of disastrous winters and disappointing harvests, the tithes the Martins collect every spring don't go as far as they used to. From the outside, the tower is an unassailable fortress, standing tall and proud as a monument to the centuries of the Martin family history. From the inside, it's a huge, drafty lump of stone full of rooms no-one goes into anymore. The entire population of the castle today is the Lady Lydia (may songs ever be sung of her great wit and beauty, etc), Jackson, trainee knight and all-round bastard by profession, a single cook and a single ladies' maid, both of whom are presently barricading themselves in the kitchen, and himself and Scott, whose poorly-defined servant roles have stretched so far as the rest of the staff dwindled that even Jackson can't get much mileage out of rubbing their faces in it anymore. It's the dead of winter, they're leagues behind the front line, the tower's supposed to be unassailable and _no-one_ without the supervision of a master hunter would be out travelling by choice this time of year. Sure there's only six people left in the tower – three of them women and one of them Stiles – but they should have been _safe_ here. 

It's a little late now to realise they never allowed for an enemy who could _fly_.

Now Scott's out hunting the hunters – and if anyone could find and reach them in time, Scott's their man – but even if he can pick up their trail, there's no reason why they should be inside of two days ride from home yet (and at least if he can't find them, no-one will have to deal with explaining _how_ Scott would be able to pull that off in the woods in the last grasp of winter, but that's pretty cold comfort right now). Jackson… well, if Stiles knows Jackson, he's probably hacking the snot out his training dummy in a fit of macho bullheadedness, like someone who _didn't_ have to have a dislocated shoulder shoved back into its socket last night. Stiles is probably going to find him passed out on the floor in pain when he looks in there next, which is the sort of image he'd get a whole lot more satisfaction out of on any day but today. Stiles himself, meanwhile, wasted two hours from first light this morning hunting through every last bag and jar in all his stores without finding enough fresh mountain ash to put a ring around a jewellery box, and the rest of the day on the edge of a panic attack that never quite wants to either happen or go away, stuck in this room with his useless books that won't tell him anything except _you are so, so screwed_. And Lydia still won't wake up. 

The morning's furious research binge did turn up a few relevant odds and ends. He knows incubi are unheard of this far west – which is making Stiles feel _so proud_ of their history-making new discovery, seriously. He knows that if the incubus got far enough doing its… _thing_ to leave Lydia in a coma, then she's officially 'in its thrall' and not going to wake up until someone either kills it or drives it far enough away to cross running water, which they aren't likely to find anywhere closer than the _ocean_ at this time of year. They have probably at least seven days before she wastes away altogether, but that comes in at just about the least of all concerns on Stiles' list right now. Tomorrow night is the full moon, and if the incubus thinks it can take on Scott at the peak of a werewolf's power, Stiles would be only too happy to watch it try. The night after that the hunters are due back (and they'll _be here_ ; Stiles won't let himself believe anything else). If they can just hold it off for one more night they might just make it. But they're not going to, because once an incubus has an innocent young lady in its thrall it _will_ be back for her, and Stiles has this hunch it's not the sort to go in for long courtships. 

Every time he closes his eyes he's still seeing the look on its face in the moonlight, remembering the dark shape of its body perched over Lydia with a claw clutched against her throat. Even while Stiles watched it dislocate Jackson's shoulder and throw Scott clean across the room with one hand it never had to let go, hardly even shifted its weight, all while Stiles stood there in the doorway feeling every last ounce of how uselesshe was to anyone. The way it had grinned at them, with teeth like interlocking shards of ice. Stiles is under no illusion that when it dived back out through the window and disappeared it was a retreat. It hadn't taken the space of ten seconds for it to prove how little it had to fear from them; if it left, it was only to grant them the gift of twenty-four hours to do exactly what he's doing now, stewing in their own helplessness before it comes back to finish the job. 

Stiles has exactly zero doubt that it's going to be back tonight, and after what he saw it do to Scott and Jackson yesterday, he has exactly zero confidence they're in any way prepared to stop it.

The only thing in his research that comes close to a working strategy comes from his book of _poetry_ , of all credible sources – a poem recounting of something that does actually sound a good deal like the predicament they're in now. The poet has gone into such graphic and florid detail on the subject of exactly what the demon is going to do to the innocent maiden in question that Stiles came away from his first reading with the awkward feeling he knows a little too much about what the guy was doing with his other hand while working on it. The only reason he's willing to give it any weight at all is that the description of her rescuer's attempts to wake her sound a bit too close to what Stiles has been through today to put down to lucky accident, so just _maybe_ under all that pretension there's something in it that really happened. It's even a tale that supposedly ended with the death of the incubus, but Stiles would find that a lot more exciting if the method that supposedly got the result didn't sound like exactly the sort of folklore that would opt to cure a bad cold by covering a man in leeches and hanging a newt around his neck. Stiles currently has it sorted into 'last ditch resorts'. 

He wishes he had a little more hope of finding anything better before the sun goes down. 

* * *

Jackson's not passed out on the floor when Stiles goes to look in on him later, though he _is_ crouched in a corner looking like he wants to throw up, and not even in that normal way he look whenever he notices Stiles is around. Today, Jackson hardly looks at him at all, eyes skating straight over him to land on Scott, who shakes his head and repeats what he'd already told Stiles the moment he got back. 

"Nothing. I couldn't even find the scent."

Jackson's eyes roll up toward the ceiling. "Of course you couldn't."

"I circled my way out from the tower for hours," Scott insists. "It snowed three times since they left, all the tracks are gone."

For one awful moment Stiles is sure this is about to erupt into a tide of useless recriminations, but all Jackson does is shove himself to his feet, wincing so badly when he forgets himself and tries to support his weight against the wall with the wrong arm that Stiles' own shoulder twinges in sympathy. He wobbles his way to the door, looking not even half as steady as he's trying to, and shoves his way past them without a word. 

The silence hangs between the three of them until they've followed him all the way down to his quarters, where Lydia's waiting for them laid out on Jackson's bed. It was one of few things they'd all agreed on last night that no-one liked the idea of leaving her in the same room where she was attacked, and like it or hate it, of all the rooms in the tower that had been dusted in the last year, the quarters allocated to the knights in training had the thickest walls and the smallest windows. There's a joke there Stiles would ordinarily be longing to make about how _this_ is how Jackson finally gets Lydia into his bed, but today even that's ruined for him. 

Right up until they get there there's still that tiny hope in the back of Stiles' mind that just maybe they've got it all wrong and Lydia will be waking up – the incubus will have starved out in the cold or found the hunters all on its own, and she'll be fine and _nothing_ will be coming after them tonight. But it's a hope that's already fading the moment he sees her, and by the time Jackson's knelt down by her bedside and put a hand on her arm without getting so much as twitch of an eyelash from her, that hope's long dead. 

Jackson looks away from the bed. "Okay," he says. "It's simple. Me and McCall," he jerks his chin at Scott, "we barricade ourselves in here tonight. _If_ it finds us, and _if_ it gets through, we'll be ready. We scare it away, same as we did last night."

Scott's mouth drops open. Even it's plainly just bravado making Jackson talk like that, Scott's nowhere close to ready to hear any part of what they'll have to deal with tonight called 'simple'. "Jackson, it's not going to make it that easy for us a second time."

"How do you _know_ that, McCall?" says Jackson, and oh god, thinks Stiles – they're all so geared up to fight _something_ they're going to end up fighting each other. "When you took up howling at the moon once a month, did you pick up some kind of insight into everything else out there that goes bump in the night? Is that how it works?"

"It could have killed us last night," Scott argues, "the only- "

"Then why didn't it?" Jackson raises his eyebrows at the both of them like he thinks he's said something terribly clever. 

Now Stiles can't help his eyes from rolling. "Jackson-"

"It saw a _werewolf_ ," snaps Scott, a fraction too late to convince anyone he's not pulling this off the top of his head. "It thought the rest of the pack couldn't be far behind! By now it'll have figured out that's not true."

"And when the night didn't break out in howls the moment it left, how come it didn't come straight back then, huh?"

"Jackson, both of us together couldn't land a hit on that thing!"

"Do you have a better plan, McCall? Because if you do I'm all ears."

" _I_ have a better plan," says Stiles, before he can think better of it. 

They both stop and stare at him – which, great, that was exactly what he was going for, but as usual, Stiles hasn't entirely thought through what happens next.

"You do?" says Scott. Considering that Stiles had told him basically the opposite not fifteen minutes ago, Stiles probably deserves the wounded note in his voice there.

"Well. Maybe _plan_ is too strong a word," says Stiles. "I might have found something in one of my books."

"You _might?_ "says Jackson.

"Why didn't you say so?" says Scott.

And that's how Stiles winds up proposing a plan he chanced on in a book of old poetry that he can't even remember why he picked up to begin with. 

* * *

It's going to have to be Stiles. That much actually gets decided with almost zero argument. Jackson has the kind of masculine jawline that people who barely know him can recognise at fifty paces, and none of them imagine for a second that an incubus wouldn't notice straight away the comely maiden it was expecting has been switched out for a _werewolf_. Even better, that means the both of them will still get their chance to barricade themselves in with Lydia as a fall-back plan just in case this doesn't work. _Two_ plans Stiles wouldn't willingly bet his life on – let alone Lydia's – have got to be better than one, right? 

He takes one look at himself in Lydia's lacy night dress and wants to laugh hysterically. He can't though, because Scott's still here, and Stiles is painfully aware that the only reason he agreed to this plan at all is because Scott trusts him with the kind of fervour that Stiles can't even deal with right now. One hintthat Stiles is in over his head and he's not going to let this happen. He has all these questions, is Stiles sure there isn't some kind of ritual they have to do first? Is this going to hurt Stiles? How far is he going to have to let the incubus get to make this work?

"I don't know; can we _not_ talk about this?" Stiles begs him. "I'm freaking out enough already. Don't you have something else you should be doing?"

Scott looks guilty, and a little hurt, but mostly like he thinks the right thing for him to do is stay and provide moral support, even though Stiles was very serious about how he can freak himself out plenty enough without outside help. Oh god, is he going to have to play the 'ruining my one chance to save the life of the woman I love' card just to get rid of him?

"How about he gets those wolf-muscles busy downstairs moving all that furniture we need shifted?" says Jackson, loitering in the doorway. His tone suggests very little patience with how the job's not been done by now, if not hours ago. 

Scott bristles at him in that special Scott way that means he's about three seconds from popping claws, and as much as Stiles needed the interruption, he can't exactly blame the guy. Jackson's right – it's a job that needs doing and Scott's the only one in any condition to do it – but being Jackson, he's still managing to be an ass about it. Doesn't help that he's calling Scott out to work on the back-up plan that won't matter unless Stiles' part goes horribly wrong, and there's no part of that that looks good for Stiles. 

But he needs Scott distracted right now, and the last thing any of them need is another fight, so what he does is put a hand on Scott's shoulder and say his name. Scott jerks under his touch and looks at him. 

"It needs doing," Stiles reminds him, nodding his head toward the door. 

Scott nods grudgingly, and stalks out, glaring at Jackson until he's out of the room. The sound of his footsteps on the stairs gradually fades into the distance. 

"So," says Jackson, and Stiles isn't even looking at him until he hears the note in his voice, "where was it you said you ran into this plan?"

Stiles gapes at him. Jesus, et tu, Jackson? If he doesn't need this from Scott then like hell he needs it from the guy who's been holding Scott's secret over their heads for months, and he's half a second from explaining that before he actually looks at Jackson properly and the challenge he was expecting to see in his eyes isn't there at all. He's not even really looking at Stiles, and the tension in his shoulders, running all the way down his good arm, says this isn't Jackson being dismissive. He's having actual trouble maintaining eye contact while broaching this with him.

Stiles knows Jackson does not give a shit about him. If he thought feeding Stiles to the incubus was all it would take to save Lydia's life he'd be the first one on board (and Stiles – he might just be the _second_ , damn the both of them). When he explained this plan downstairs Jackson made it pretty obvious the only reason he was going along with it was to humour the guy who didn't have any other damn thing to offer anyway. 

This? Is nothing Stiles expected. He gives in; blurting out, "It was in a book of poetry!" is so much easier than processing the rest of this. 

Oh, _now_ Jackson's looking at him. " _Poetry_?"

"It wasn't the only place I've heard of it!" It's true – he might not have remembered it without the poem to jog to his mind, but the idea wasn't completely new. He thinks.

"Oh yeah?" says Jackson. "Where else?"

"I don't remember! Just that I've heard it somewhere and – maybe it was something Deaton told me." Stiles scrubs a hand through his hair. "It makes sense! Incubi are all about life and death and sex. If you trick one into trying to drain the life out of someone who's the opposite of what it expects, maybe it all goes backwards. It fits!"

Jackson looks like an illustrative demonstration of the word 'skepticism', but eventually he nods. It's a short, stiff movement that reminds Stiles far too much of Scott's body language from moments ago than he's comfortable with. 

"So just for the record," says Jackson, "how sure are you you're going to live through this?"

"Well. 'Sure' might be the wrong word," Stiles admits. 

"So if it doesn't work…"

"Not really thinking about that part, thanks."

"And if it does…?"

Stiles hesitates. "The poem didn't go into a lot of detail about that option either."

Jackson gives another couple of those stiff little nods, gaze fixed firmly on the doorframe. "Is there anything else you need?"

"No, I think I'm…"

"Anything you _didn't_ tell McCall," Jackson clarifies, and that actually shuts Stiles up completely. He thinks – probably – there should be something, but he can't even think about what it means that Jackson's offering. What it all comes down to is that Stiles thinks that if he does this, he has a shot at saving Lydia, and Jackson knows he's so far out of his depth here that he's not even going to question that. 

Stiles shakes his head.

"Okay," says Jackson. He opens his mouth again like he's about to say something else, but then he stops, turns in the doorway and leaves without another word. 

A few moments later, Stiles will realise he doesn't even remember the part where his legs gave out and deposited him onto the edge of Lydia's bed like a sack of potatoes. 

Who'd have thought all it took was one shared experience of having to survive an assault from an evil sex demon to break down the boundaries around here? Maybe if they make it through the night Jackson'll stop calling Scott by his last name and bother to remember how to pronounce Stiles' and they'll all be laughing about this around a campfire by spring. Then Lydia will fall madly in love with him and he'll invent a new invocation to repair next year's weather and single-handedly save the harvest and unicorns will frolic through the woods.

What? It could happen.

* * *

Stiles is not actually counting on the incubus being so starved for affection when it turns up tonight that it would completely miss how the person in Lydia's bed isn't Lydia. Hence the nightdress, not that it's really in his size (or his colour), but he's not that much larger than her, so it could be much worse. He's also going to be wearing a funerary veil – which isn't so much conventional sleepwear, but supposing they really were the sort of cowards who'd give in and leave Lydia up here to her fate, adding the veil to her ensemble makes a certain symbolic sense. Stiles has already teased several long strands of strawberry-blonde hair out of Lydia's comb, and he figures if he lays them out so they peek out of the bottom of the veil then the illusion will be… okay, not complete, but a reasonably promising work in progress. 

What's going to make the illusion complete is the pot of incense that Stiles is about to light and leave burning at the bedside. He may be a mere fourth-year apprentice who only gets instruction for two months out of every twelve and who isn't even allowed a real bestiary yet, but the most basic of all basic glamours – the kind that does no more than encourage the subject to see what they were already expecting to see – that he can pull off with a little smoke and some nightshade and juniper bark in a bowl. 

See, he's got this all planned out. And the longer he makes himself focus on getting his plan in order, the longer he can put off the part where he realises what he's got himself into and panics. 

Unfortunately, fiddling with the veil in front of the mirror to find the most covering arrangement is a total non-starter of a distraction, because hello, veil + candle light = a perfect recipe for next to zero functional vision. Lighting the incense is the work of ten seconds. And arranging himself in Lydia's bed while Lydia's not even _here_ is… well, under the circumstances everything about the exercise is so mind-blowingly _wrong_ that dwelling on it is only going make things worse. Also, he's been told he snores, so going to sleep while he pretends to be Lydia's unconscious body is right out of the question. 

Good thing Stiles wasn't counting on getting any sleep tonight. 

Two seconds after he's finished that thought he realises how that would sound if you _didn't_ already know he's talking about lying here for hours paralysed with skull-crushing fear,and lets out a yelp of laughter that would definitely have blown his cover if his visitor had been here yet. Stiles slaps both hands over his mouth (outside the veil, thank you very much) and chortles in a silently hysterical manner until he feels tears start to seep out of his eyes. Oh god, what is he even _doing_? Playing bait for a _sex demon_ that is probably going to laugh in his face before murdering him in Lydia's bed? 

The cloying scent of the incense is starting to spread through the room now. It's supposed to have a calming effect, but Stiles would have to say he's really not feeling it just yet. 

Okay. Okay. Calm down. Think about this reasonably. They haveto give this a chance to work. What's the worst that could happen?

Well, logically, the worst that could happen is that it rapes Stiles to death, then goes downstairs and kills Scott, kills Jackson, then wakes Lydia up just long enough to show off all its handiwork before it…

Alright, on reflection, that isn't such a helpful line of thinking. The thing to remember is that if they hadn't gone for Stiles' plan, the worst cast scenario would still be the one where it not only gets to Lydia, but murders the rest of them too just because it can. So it's not like this is any worse; nothing ventured, nothing gained, right? 

After a few minutes of trying to make himself believe this, Stiles has to admit he'd have a better chance of convincing his gut to buy that one if his brilliant plan _didn't_ involve effectively offering himself up to a murdering sex-demon on a platter. 

Okay, focusing on the worst case scenario isn't all that comforting. Time to try best-case instead. Best case scenario: the incubus touches him and falls dead on the floor. Perfect! No mess, no fuss, Stiles saves the day. 

Somehow his gut doesn't seem to be buying that one either. 

Stiles takes a deep breath and tries out something more believable. 

The incubus does… does its thing to him – the whole nine yards – but afterwards it falls off dead. 

The incubus dies, but takes Stiles with it. 

The incubus kills him but finds him so satisfying that it leaves for the night. Scott and Jackson hold out for two more nights until the hunters can come back to kill it, and everyone remembers his brave sacrifice forevermore. 

Those all settle in with Stiles' sense of realism a little more easily, though it's weighing on him like a solid mass in his chest that it's taking so much work to come up with outcomes that go well for him here. 

Hey, maybe it won't show up at all. Maybe it'll get halfway here and remember a very important letter it urgently needs to answer right away. Maybe it'll get lost or fly into a hurricane. 

Maybe it'll use its demon-senses to track Lydia straight to the knights' quarters without coming through this room at all, and Stiles will have no idea he's the last living person in this castle until tomorrow morning. 

Maybe he'll gas himself to death with his incense before it even arrives and whoever makes it out of this alive will write _here lies Stiles Stilinski, an object lesson in where a little knowledge gets you_ on his gravestone.

Well _there's_ a wagon's worth of thought that's going nowhere good.

Stiles makes himself think of Lydia – the reason he's putting himself through all this in the first place. How she looked at last year's midsummer festival, with flowers braided into the delicate weave of her hair; the way her skin glowed in the sunlight. He remembers the way he'd seen her simper and flirt with that self-absorbed prick of a visiting nobleman at the autumn feast, hanging on his every word like she wasn't longing to correct his outdated misinformation of the political situation on the eastern front and couldn't have run rings around his basic understanding of Latin conjugations, while he nattered on oblivious. ( _Stiles_ noticed, not that he'd spent his every free moment at that dinner staring at her or anything, but could he really be blamed? Once you'd noticed what was really going on under Lordling Sissypants' very nose, it was hard to look away. It was like watching a man rapt in expounding the best way of stabbing oneself in their own foot.) 

Stiles gets it – he really does. With the scandal of Lord Martin's divorce still hanging over them, the Martin family is struggling to hold themselves together in more ways than they can ever afford to let on. For Lydia to marry a rich nobleman would make all the difference in the world, but lord knows she deserves so much better than those simple fools who haven't the slightest idea just how brilliant she is. 

She deserves… god, she deserves so much better than what Stiles could ever hope to offer her even if they do both make it through the night. 

So much for that line of thought working any better for him. 

He needs to look at this differently. So the odds that this is going to be the great moment of heroism that finally makes her notice him are on the side of low; surely he can still enjoy some sort of irony that what got Lydia into Jackson's bed has now gotten _Stiles_ into hers, and every bit as pointlessly. Now that he stops to appreciate it though, this is a really nice bed. He's hardly even been allowed to touch a real feather mattress before, but he could definitely become a convert to a lifetime of napping on a few dozen pounds of down. There've got to be worse places Stiles could have set himself up to lose his virginity. 

…which is _not_ what's going to happen tonight, because being on the receiving end of an unqualified level of personal violation by an evil incubus that was expecting a girl does not and _will_ not count, unless Stiles decides it does. 

And alright, if it distracts him from dwelling on the probability of his imminent demise, maybe it _is_ time Stiles took a close look at the woolly mammoth that's been lurking over there in the corner all evening. There's a possibility – mixed in there somewhere along with all those other ways this could go for him tonight – that Stiles is going to enjoy this. _Really_ enjoy this, with all the nudge-nudge-wink-wink innuendo mental italics could hope to imply. The incubus isa reputed to be demon that exudes such an incredible aura of raw sex appeal that its victims never even notice it's draining the life out of them until it's too late. Stiles is a virginal teenaged boy with a healthy libido. He has no ideawhat's going to happen tonight, but he'd be lying to himself if he ignored that little part of him that's maybe just a little interested in finding out. 

Well. Technically speaking, he hasn't reached this age without putting together _some_ idea. What little Stiles has gathered on the subject of sex over the course of his short life includes knowing that it's not necessarily an opposite-sexes-exclusive activity. His Dad's been warning him to be careful around a certain breed of older man (the ones that smile a certain way and find excuses to touch a little too freely; the craftsmen looking for something more than talent in a new apprentice at the fair) since he was a kid. Lydia has had a starring role in his fantasy life since before he _had_ a fantasy life, but Stiles has also lived a long time now with the nagging suspicion that other boys his age don't make quite such a habit of sneaking down to watch the young knights train with their tunics pooled around their belts in warm weather as he does. So he's curious, and inclined to keep his options open. Nothing wrong with that. 

Most of Stiles is trying very hard _not_ to think about what 'the incubus has to be tricked into seducing a boy that it thinks is a girl' means for what's going to happen to him tonight, but. But he's not carved from stone, okay? Some of the flowery metaphors from that poem about what was expected to go on 'betwixt the loins' of the young lass (or lad) in question maybe did sound kind of appealing, if you turned it around a certain way. So maybe there's a little bit of Stiles that's anticipating this in a way that's not made solely out of desperation and misplaced responsibility.

Is there something wrong with him that he's thinking like that?

No, Stiles decides; no, because you know what? There is nothing wrong with thinking like that, because on the scale of all the ways this might go for him tonight, spending the experience so overwhelmed by the incubus's 'thrall' that he forgets what he's doing here is right up the top. Especially when the alternative way this might go for him, remembering the whole 'everything is opposite' theme, does not bear thinking about. 

Stiles really hopes that looking at it that way doesn't mean he's believing exactly the wrong thing to make the magic work. 

He's glad his father isn't here to see this. He hopes, a little hysterically, if he doesn't make it, that Scott will have the sense to lie about the details of how he died. 

He wishes it hadn't been so long since he last saw his dad. 

The sound of the shutters over the bedroom window being carefully pried open from the outside might just be the single loudest noise Stiles has ever heard in his life. 

Stiles' whole body is suddenly frozen to the bed. Distantly, he wonders if there's any way to tell whether you're frozen because the _thrall_ has started already or whether it's just ordinary soul-crushing terror, because if Stiles was freaking out before, it has nothing on how much he's freaking out now. The shock of cold air coming in through the window hits him like a blow; it feels like the temperature of the whole room just fell below freezing. Through the veil, Stiles can just make out the curve of the nearly-full moon peeking in under the top of the window – then it's gone, because there's something blocking the window. There's a black shape climbing into the room. Oh god, what is he even _doing_ here? The demon is here and this is really happening and _it's really here_.

He's hardly given the chance to finish that thought before the scream breaks into the chamber, so loud and so immediate that for a second Stiles thinks it's coming from his own throat. But that doesn't make sense; it's too shrill and far too piercing to have come from _anything_ human, let alone Stiles' very ordinary lungs. 

When he next dares open his eyes again the window's empty. He can see the moon again – mostly, though it blinks in and out of view a few times as though something's passed in front of it. There's something moving out there, flailing like a flag in the breeze; once or twice he could almost imagine he's caught the outline of giant wings. Maybe he hears something too, but his ears are still ringing from that scream. His _whole ribcage_ is still ringing from that scream. Stiles grips the edge of the sheets and tries to decide if he's panicking, or if he should be trying not to, or what.

By the time the ringing starts to fade there's not much to hear but for a faint rustling noise coming from outside. Then the moon is gone completely – there's something climbing in through the window again, followed by the faintest soft pat of feet hitting the floor. 

Is this something incubi _do_? Loom in your window, scream at you, flail around for a while, then come in again? Stiles' research has failed to prepare him for any of this. He wishes he felt anywhere close to being up to holding onto a coherent thought right now, because he has the horrible feeling he's missing something important. But he doesn't have the first idea what, and any lingering hope he might have had of sorting out what he's supposed to do with what just happened evaporates into the ether when he feels the end of the mattress dip under someone else's weight. 

Oh god, it's on the bed with him. Stiles' whole body goes tilting towards it when it plants a hand by his knee, and he's completely forgotten why he'd ever thought nice things about this mattress. Its luxurious texture only ensures he feels every move the incubus (which is _really here_ and _really on the bed with him_ ) makes, magnified in agonising detail as it crawls up and over him, caging him between its limbs. Touch is all he's got to follow it with; he can't hardly see a thing through the veil in this light, and certainly not once the window vanishes under the black shape which is getting closer by the heartbeat. When he spots two glowing red pinpoints glaring at him out of the darkness he squeezes his eyes shut, and tells himself the idea in his head that he can still see its eyes through his own eyelids is just his imagination. He desperately hopes his incense is working, because from the way he can hear himself all but panting for breath, there's no chance he's putting up a convincing pretence of being asleep without magical masking. 

The incubus takes forever to plant its hands by his shoulders, and then another small forever making itself comfortable, or whatever it's doing now that requires shifting its weight around so much. It still hasn't so much as touched him and Stiles is about to go mad from the waiting alone. 

" _Well_ ," says – hell, _purrs_ a voice so close Stiles can feel the words ghosting against his skin (that sound Stiles just made may have been an actual whimper). "You're not _quite_ what I was expecting."

Too late, Stiles rediscovers the ability to lie perfectly still without breathing at _all_. Something – something with _fingers_ – presses down over the middle of his chest, outside the blankets. There are several thick layers of bedclothes separating the incubus from Stiles' person in this arrangement – it's the middle of winter and hard times or otherwise, the Martins see no need to shiver their way through it. There is no natural explanation for why Stiles should be feeling the hand tracing down the length of his chest so keenly, not unless you blame it on the sensitising effect of _fear,_ and even then... god, Stiles has had firewood splinters lodged under his _skin_ he was less aware of than this. The incubus doesn't stop when it runs out of Stiles' chest, or when it reaches the base of his stomach, or when it drags beneath his pubic bone – and when it drops between Stiles' legs, Stiles is gasping aloud before he can even think to stifle it. It's not even about the pressure nearly so much as the _promise_ in that touch; like the moment right before you jump to find out whether you can fly.

Three layers of blanket might as well be made of tissue because there's no way the incubus doesn't know exactly what it's feeling down there, or exactly what it's doing to Stiles, and suddenly fear alone isn't sounding like any kind of good excuse anymore. 

"Hmm," rumbles the voice in Stiles' ear. "Now why do I have the suspicion this isn't your room?" and the last shred of hope Stiles had been hanging on that any part of his crazy plan might be salvageable snaps clean in two. "You wouldn't be the first servant offered to the beast in the place of the lord's beloved daughter. But between you and me," it goes on, voice taking on an almost conspiratorial tone, "the illusion works better when the servant _isn't_ a _boy_. Most of us _can_ manage to figure out the difference, unless…" The voice trails off. " _Oh_. _You_ thought…" 

If Stiles dies tonight, he'll go to the grave knowing the sound of an incubus _chuckling_. It's an odd, throaty hiss of a noise, and if that wasn't already bizarre enough, it almost seems to be inviting him to share the joke. 

"You know, I thought that old wives' tale had gone out of fashion," says the incubus, conversationally, dragging its hand idly over the bulge Stiles' nether regions are contributing to the contours of the blanket, and he can't help it, he bucks upward into the pressure with a gasp. There's a shimmer of movement, and the voice is even closer, right against his chin when it says, "Never did imagine I'd find someone waiting for me someday who actually bought the idea we were so _fragile_ ," the incubus strokes a hand down his cheek, over the veil, "so incurious," the hand strokes back up again, "that any one of us would shy away from the invitation to lay our hands on a fine young man. Waste of good poetry, if you ask me. You'll find the truth…" The last is whispered right into his ear, " _much_ more interesting."

Somehow, that's what does it. The incubus has made Stiles very awake and very much aware of his body, and what might be his last remaining survival instinct propels him off the bed to run for it. Or at least that's the idea, but the practice would have worked better if the incubus wasn't holding him down with such terrifying ease. 

"Oh no you _don't_ ," it purrs. Stiles struggles under its weight, but the worst of it gets muffled by all those layers of blankets, and the only suggestion that what's left is causing his aggressor any sort of grief is a short, impatient sort of sigh, that Stiles feels as much as he hears it, a gust of air through the veil against his cheek. 

"Don't be like that," it says. " _Humans_. So caught up in what you think you're seeing you never even notice what's really there."

Two things happen in quick succession; the first is the incubus shoving Stiles' incense pot off its rest by the bed to clatter onto the floor, spilling its embers onto the stone where they quickly extinguish in a last plume of smoke. The second involves the veil being ripped away from Stiles' face, giving him his first clear view of the room since all of this began. 

Last night, when they'd burst into Lydia's room, so much had happened so fast that Stiles never had the chance to process more than his broadest impressions. (The black shape perched over Lydia's body. The red eyes glaring out of the gloom. The white teeth in a twisted grin, laughing at them even as it fled.) Stiles never had got as far as thinking about the incubus as having anything as ordinary as _facial features_ until he looks at it again now and they're all _wrong_. The incubus he's looking at now looks younger,for a start. The jawline is sharper – the shape of its eyes, the curve of its lips – everything's different. 

Under the glow of the moonlight it's not even completely black, now he's seeing it without the veil in the way. Its wings are shot through with a fascinating purple sheen that glistens when it moves, and its body is flecked with the same colour in strokes like an artist's shading lines. Over its face and chest even the purple gives way to the hue of human skin; darker than Stiles' own, but no more so than the colour some of the knights take on after a few weeks of training stripped to the waist in the summer sun. The comparison falls a little short there, however, because it doesn't seem right to compare this physique to theirs; the incubus's body isn't just broadly humanoid, it looks like a living _sculpture_. Hadn't it been all black last night? Stiles doesn't know what he's remembering anymore. 

"You're not…" he breathes, but already he's second-guessing himself. Is this something incubi can _do_ , change how they look to confuse their victims? Did it find someone else to drain the life out of last night, is that why it looks younger? (And why it looks so _preposterously_ healthy?) But it's a little hard to concentrate on suspicious hypotheticals when the overwhelming impression is, "You're really attractive."

The corner of the incubus's mouth quirks upwards, and Stiles' heart skips a beat. It looks pleased. Oh god, Stiles made it _pleased_ and he is in _so_ much trouble if he's so happy about that. "You get that all the time, don't you?" he babbles. 

This time it's less of a quirk of the lips and more of a slow rise of both corners, which lasts as the incubus leans down on its elbows, hovering over Stiles' face. "Why don't you tell me your name?" it says, like Stiles is stupid enough to give his name to a dangerous mythical being. 

"It's Stiles," he says. Ha! It's not like that's his real name. Mythically speaking that doesn't even count. 

" _Stiles_ ," echoes the incubus, and the way it makes that sound is a shiver that runs the whole length of Stiles' body. "Alright, Stiles. Here's how this is going to go. You and I are going to have _sex_. And while I'm making you come harder than you ever _dreamed_ of coming before, I can drain the last drop of life out of your body – _or_ you can swear to me you'll never to breathe a word of what happens tonight to another living soul, and I'll let you live to keep your word. Your choice." 

"What?" Hearing the incubus say 'sex' may have fried what little of his brain was left (and if that was an accident, then Stiles is a werewolf), because Stiles could have sworn it just offered him a _choice_. "Is this a trick question? Please don't take that the wrong way." So tonight has already proven Stiles is no expert on all things incubi, but he's pretty sure they don't do this. They don't leave their victims alive, they _don't_ give them choices. 

"Obviously," says the incubus, like the smug bastard that it is. 

"Ugh, you're a legendary sex demon, of course it's a trick question!" He's babbling to clear his head and buy himself time – which the incubus actually seems to be giving him, going by the way it's shifting its weight to one arm and hasn't demanded an answer immediately. Okay. Stiles knows this stuff. Contracts with demons are serious business and dangerous territory, and Stiles has zero leverage. It's messing with him. It's not even pretending not to be messing with him. Odds are it's not going to honour either choice and this is all part of the same thing it's doing with its face – lulling him into a false sense of security to make him more pliable. In fact, that's probably the _best_ case scenario. "Can I ask a question?"

"Long as you understand I don't promise an answer," says the incubus, shrugging a shoulder, which is probably the best Stiles could have hoped to get. 

"If you don't kill me, are you going to kill someone else instead?"

"Hm," says the incubus. "No."

"No?"

"That's your answer."

Stiles swallows. "Am I going to- "

" _One_ question, Stiles," the incubus reminds him. "Now choose."

None of this is fair, but it's not like he came in here tonight expecting fair play from an incubus. All he's sure of is that giving a demon permission to kill you would have to be the height of insanity, even when you _know_ it's trying to trick you. 

"Um. I'd really like not to die tonight. Or any time soon, if that works for you," he says, then kicks himself mentally. What is he, stupid? "Actually, even if that doesn't work for you. The option where no-one in the tower dies tonight and you just _leave_ when you're done with me is the one I'm choosing. If that's what's on offer." Okay, that's a little better. 

The incubus runs its tongue over its teeth, capturing Stiles' attention in a way that knocks the breath out of him, and it says something that might be, " _Excellent_ choice, Stiles," but he's not entirely sure because that's when it kisses him and he starts losing time. 

He loses quite a lot of time there, actually. Probably. It's hard to tell.

He doesn't get it back again until _that mouth_ is leaving his. Until he's _not_ being opened up under its tongue, the incubus learning him from the inside and inviting Stiles to do the same; _not_ discovering in an endless rush just how sensitive his lips truly are. No-one has ever kissed Stiles before and he doesn't want the incubus _not_ to be kissing him, possibly ever again. The moment it leaves he's chasing it up and away – _can't_ let it get away like that, and wouldn't be except that there's something pressing him gently but firmly down into the bed, shushing quietly in his ear. 

"Easy," the incubus whispers, like that word means anything to Stiles anymore, "we've got all night." 

"Oh my _god_." Coming back down to where his brain can understand words again, Stiles has a flash of understanding, and suddenly he _knows_ on a horribly intimate level how what they're doing here can kill people. It's dawning on him that if that offer really was a lie, this might not be such a bad way to go. And because Stiles is Stiles and he wouldn't know how _not_ to get ahead of himself, it's sinking in that that might be a mercy, to have had this and then not have to deal with the possibility of there being a time when he _doesn't_ have this – what's going to be the rest of his life if he makes it through tonight.

There's a flash of white above him – _teeth_ ; not fangs, the incisors are hardly even pointed; this thing has teeth like a human and he doesn't even know why that knocks the breath out of him all over again and delays where he puts it together that it's _grinning_ at him another several seconds longer than it should have taken. He doesn't even know what to do with that, except that he's got the idea it can see him in this light a lot better than Stiles can see it, can probably see right through him and it... oh god, it _likes_ what it sees. 

"Gooood, isn't it?" says the incubus, dragging out that vowel to a length that is fucking indecent; the way it's _talking_ instead of doing fucking indecent things to Stiles with _that mouth_ is fucking indecent, and if Stiles wasn't next to sure the damn thing is reading his damn mind already and knows perfectly damn well what it's doing to him, he'd tell it that. Somehow. 

"Oh yeah," he breathes. By his standards, that has to count as positively speechless.

The incubus runs a finger along the edge of the sheets lying over Stiles' chest. "Why don't we get these out of the way?" 

Stiles is completely on board with that. 

The bedclothes do not go without a fight, Stiles pushing while the incubus pulls. Most of the layers are firmly tucked in underneath the combined weight of the mattress and his body, and by the time it dawns on him he could have saved a lot of fuss by removing _himself_ from underneath them rather than the reverse, they're too far into the job of tearing the bed apart to change strategy. The air outside is a shock of cold against his skin – it's a freezing night and only worse for the window having been left open – but the worst of it fades quickly. Mostly he decides that's not worth questioning; maybe incubi radiate warmth, or mess with your metabolism as well as your better judgement, like how… holy… _what_ is he _doing_? Was he seriously just about to climb out of bed of his own accord to let it get at him? 

Stiles looks down at himself, then up, then down again. "You're letting me move now?"

"They always think you're going to do all the work for them," mutters the incubus, balancing its weight on one side and tossing the last of the blankets away, though there's not a lot of bite in its tone. It hops back over him, looming large and so tantalisingly just out of reach. "Why shouldn't I?" The incubus digs a finger into the hollow over Stiles' collarbones and drags it slowly up his neck, under his chin; dragging the whole universe down to that one point of contact. "You planning on running for the door?"

_No._ God _, no,_ thinks Stiles. What he says is, "So you can drag me back here again?"

"Maybe I would." The incubus runs a knuckle curiously down the side of his neck; breathes out a moist gust of warm air over the same place, and Stiles forgets he was ever cold. "Maybe I'd let you go."

" _What_?" says Stiles.

"Maybe I'd leave," repeats the incubus. "That's what I agreed to do, when we're done, right? You're not the only warm body on this side of the country, Stiles." The possessive curl of the fingers of its other hand around his wrist make a lie of the threat, but the very idea still makes Stiles' blood run cold.

"But you said… you just made…" he stutters. "Oh you _evil_... you _are_ evil!" 

The incubus laughs, draws the captured wrist to its mouth and sinks its teeth ever so lightly into the soft skin beneath his palm. His hand is so close to its face; it's had its hands all over him and Stiles hasn't even been allowed to touch it yet. He watches his fingers twitch involuntarily. 

"You want me to hold you down while we do this, Stiles?" says the incubus, cheek turned into his palm. The curve of its brow is hovering just under Stiles thumb, if he bent it just a little…

In one sudden movement the incubus has Stiles' arm wrenched over his head and pinned it by the wrist below the headboard. "Would that make this easier for you?" 

Stiles swallows and accepts that his heartbeat isn't about to slow down again any time soon. "Maybe?"

"You really think that's what we do? You think we _need_ to? Ever?" (Actually, Stiles has half an idea that 'thinking' isn't much of good description of anything that's gone through his head for a good few minutes. It's so unfair of it to pick on him for that.) "We get our hands on a virgin teenaged boy, and we waste our strength _holding him down_ while he begs us for it?"

Stiles gets momentarily stuck on the word 'virgin'. "…is it that obvious?" Possibly he's trying to prove how not up to thinking he is anymore. The incubus raises its eyebrows at him.

"What do you want, Stiles?" it purrs. "You want me to leave? Or do… you want… _me?_ "

In some tiny, distant part of his mind, Stiles thinks _this is how it starts_. He admits to wanting this, he agrees to more, and within an hour he'll be begging it to take his life just as long as it lets him _come_ before it all blacks out. If he said no they'd both know he was lying. 

But miraculously, the incubus takes pity on him, curls a hand under his head and kisses him again until Stiles can hardly remember the question, let alone whatever he was going to say. This time, when it pulls away it does so with a slow drag of teeth over his lower lip that makes his eyes flutter closed; distantly and stupidly proud that this time he doesn't end up trying to chase after it for more. See? Self-control. Like it said, they've got all night. So what if Stiles doesn't have a chance in hell of lasting that long. 

His eyes fall on its chest when he opens them, leading to a snap realisation that he hasn't spent nearly enough time appreciating it yet. The flush of pale-coloured skin that makes up the incubus's soft underbelly is hopelessly mesmerising; it almost glows in the moonlight. He still can't get over how _human_ it looks – it has _nipples_ , abdominal muscles, a belly-button – his fingers itch to touch; it's on the tip of his tongue to ask for permission, but the words get stuck there as his eyes dip lower still.

_Oh_. That's. That's its _cock_ , curving thick and hard up beneath its stomach. Are incubi always like that or is it… is it hard because of _him?_ Why is he still thinking of the incubus as an 'it' when he has no possible doubt left about its physical sex?

The incubus makes a noise that just about passes for a polite cough. Stiles whips his attention back to its face and says, "Um." 

"Now you've got me at a disadvantage." The incubus turns its attention down to the nightdress Stiles is still wearing. He'd swear the look it flicks up at him clearly spells every last thing it's thinking about his choice of night-wear, and he has his mouth open to defend himself before it takes one long claw to the bodice and _rips_ the whole dress clean down the middle.

Huh. Claws. Handy, Stiles thinks, vaguely. Wait, didn't he…?

The incubus flicks another look at him and grins at him for a second (it has _fangs_ , what…?). It dips the tip of its index finger, the very point of its claw, into his naval, ever so gently, then drags it back up the line of the centre of his chest while Stiles tries very hard not to breathe. He doesn't know whether to believe what he's feeling until the incubus flicks its finger up again off the top of his chest, showing him a neat, blunt nail.

"Nice trick," he offers, weakly. Then, "Oh, Jesus," because now the incubus is following that same path with its _tongue._

By the time it gets to his neck and applies that terrible mouth sucking a kiss beneath his ear, Stiles is losing time again. He remembers reaching for it at last, getting his hands up behind its body, feeling the shape of its wings where they curve into its shoulders; its skin is so smooth and warm, like nothing he'd expected; the thrill when it _lets_ him tug it down, draw them together. He remembers the drag of teeth along his jaw as they line up against each other, as the incubus eases its chest down against his own. He remembers the touch of a hand tracing down his side to dip into the crease of his hip, tracing the flesh of his inner thigh until he almost goes mad from wanting; until stroking turns into guiding his leg up to hook around the back of its knees and wrap their bodies into each other, so Stiles can finally thrust up against it. He loses everything for a while after that, until it rocks back down and shows him how to find a rhythm, and kisses him again at last, and Stiles knows he's ruined. He's never done this before with anyone and nothing is going to match up to this ever again.

When the incubus murmurs, "Like that, don't you?" Stiles should have had a smart reply ready – is sex with him so mind-melting the best it has left is mastering the obvious? – but he's so far past that now. He's not just ruined, he's _wrecked_. How hasn't he come already? He whimpers and bucks up, harder, trying to get closer, but the incubus' fingers are back on his thigh, holding their distance and it rides out the motion easily. "I _need_ …" he begs. 

"Shh," whispers the incubus, and Stiles wants to laugh at it. So he does, or he _tries_ , the sound stuttering out when it releases his thigh in favour of wrapping its hand around both of their cocks and stroking them together. Stiles forgets how to breathe again, which doesn't work so well because – forget _shushing_ him – Stiles just lost all the air in his lungs yelling or moaning or whatever that noise was and he doesn't know what to do next. The incubus's rhythm feels calculated to wring him dry. Fuck, it's hardly a rhythm at all – it's making him wait what feels like eternity between each sharp, upward tug, gliding its hand back down so horribly slowly in between. There's a slick moisture coating them both; Stiles almost decides it's his own semen except that he can't have come yet, how could he have come and still be so hard?

"Patience, Stiles," the incubus whispers to his skin. Stiles gulps for air. 

"How have I not come yet?" he says – he will _not_ let it be a whine. "Are you… is it you? Are you not letting me, with your incubus-thing?"

"Am I going to have to explain 'patience' to you?" says the incubus, though it would be a lot more convincing about losing patience with _Stiles'_ impatience if it didn't sound so pleased with itself. "You haven't come because we're. Not. Done. Yet."

Because it truly is evil and clearly wants Stiles to know it, the incubus lets go of him, trailing its hand lower, over his balls. Before he can protest or offer it his firstborn or whatever was about to come out of him, it thrusts savagely down into his body and while he's still reeling from that, it finds a spot behind his balls Stiles would swear didn't even _exist_ before today, and presses on it until it makes him keen. "Do you know _why_ we're not done yet Stiles? Do I need to explain that to you too?"

It thrusts _again_ and the only thing left grounding him anymore is its voice in his ear saying, "We're not done because _I'm_ not ready to come yet. And I'm not going to be ready to come until I'm inside you." And it's _still_ rubbing on that spot but there's another finger exploring further back still, it's teasing at his… oh. The only coherent thought in Stiles' head while the incubus' finger slides inside him is that apparently everything he wasn't sure he'd understood about what those shifty older men might want to do to him was right. Good for him?

Stiles says, "Oh god." He says, "Oh god, you're going to…?" 

"Mm-hm." The incubus twists its fingers. Stiles lets out a sob. 

"Do it," he begs. "Please, do it, just do it already!"

"Are you sure you're ready for that, Stiles?" 

Stiles has no idea what it means; he's been ready for this _forever_.

"Yeaaah," groans the incubus, "you're ready," and it's moving, shifting their positions, it's got its hand on his hip now and it doesn't waste a second lining them up, just sinks its teeth into his shoulder and thrusts, and Stiles is pretty sure he actually whites out for a moment.

" _Stiles_." It's the stutter in its voice that makes him open his eyes again. His name on its lips was a hiss and a moan and when he looks it in the eye again, _god_ he wasn't wrong. Are they both shaking? It looks like it's barely holding itself together, like the only air in the room it can get to are the panted exhales from Stiles' lips. It's inside him, it's hitting that same spot from the _inside_ and he almost doesn't care because just the _idea_ of what it's doing to him has him in pieces. 

He… fuck, he'd wanted this to be _over before_ he got to have this? What if it had listened? What was _wrong_ with him?

He watches as the incubus gathers itself, draws its lips in one last feral grin and then it pounces. Locks its mouth on Stiles' and thrusts into him with a fury he doesn't have words for. Stiles is dimly aware of one of his legs wrapped tight around its waist; the other lying sort of awkwardly loose, and there's no way he's built to take this sort of battering without feeling it; of its hands, one wrapped around his neck and the other into his side, then clenched in the mattress either side of him when kissing becomes too difficult for either of them to keep up. None of that matters to him worth a damn. The way it _feels_ – it's not being gentle, it's not going slow; there is _none_ of that agonising teasing from before. Every thrust sets his whole body on fire, lit up with sensation he's sure he was never even built for. Stiles is beyond losing time; beyond it and somewhere in the land of perfect clarity on the far side where he's aware of everything and it's taking all he's got to keep hold of half of it. His whole _life_ has been building up to this moment and it can't last long enough. It said they had all night and he wants that – he doesn't care if it's impossible – he never wants this to end.

He watches it arch above him, mouth wide, wings spread, before collapsing back down into him. 

" _Stiles_ ," it whispers, one last time. It sounds _broken_ , and god, he doesn't even know its _name_ ; how can they have done all this and Stiles doesn't even know his…

(Coming under the incubus's hands is such absolute bliss, so endless and so consuming that this time, Stiles really does black out altogether.)

**Notes for the Chapter:**

> To see what was happening to Lydia at about this point in time, see [The Night-Mare](http://archiveofourown.org/works/2799488).


	2. Chapter 2

**Notes for the Chapter:**

> Thanks go to Emily for her help coming up with a (we hope) plausible Latin title to appear in this chapter (though if anyone better qualified still wants to correct us, we can only admit that first year Latin only gets you so far).

Stiles wakes up the next morning to Scott shaking him by the shoulder and calling his name. This can only mean his idiot of a best friend has forgotten there hasn't been anyone in the tower in months who cares one way or another whether they're up at the crack of dawn, and he's wasting a perfectly good chance to sleep in. Maybe if Stiles lies here and ignores him a little longer he'll figure that much out on his own and go away, leaving Stiles to snooze another half hour and bask in the tail-end of that amazing dream he was having. He can't remember the last time he felt this warm or comfortable and Scott has no right to ruin it for him.

"Stiles!" Scott's saying, "Stiles, _Lydia's awake!_ "

The words hit Stiles like a bucket full of ice. He sits up so fast he almost gives himself whiplash. "Lydia?" he croaks.

"She woke up!" Scott repeats. "About an hour ago. Jackson wouldn't let me leave until dawn, he thought... Stiles, what happened? Are you...?"

Stiles hurriedly rubs his eyes and sits up. What's he supposed to tell Scott? That he spent the whole time getting a great night's sleep on Lydia's wonderful mattress, with nothing more unusual to show for it than the best dream he's had in... oh _holy_...

Did that really _happen_?But... he's alive – he's fine – he's not even aching anywhere; if all that happened for real he'd at least still be feeling it, right? He's neatly tucked into bed; his incense pot is sitting on the stool beside him in perfect order, and the shutters over the window are closed, the only light in the room coming from a lantern on the floor by Scott's feet. Stiles' hand goes to his shoulder – the incubus _bit_ him there so hard it would've had to bruise, but there's nothing. He tugs up the blankets and looks down at himself. There's not a mark anywhere on his body – which he can see, because the lacy nightdress he's still sort-of-wearing has been _ripped in two_.

"Oh my god," he says. "That was _real?_ " He badly needs a word for that thing that happens when some detail of a dream you'd almost forgotten on waking grabs you by the toes and the whole incoherent narrative comes crashing back over you, because he's experiencing the hell out of it right now, with the added _aaargh-_ factor of it _not being a dream_.

Scott swallows, his face the perfect picture of the same concern that Stiles is feeling knotted in his chest like the prelude to a heart attack. They must make such a picture.

"Is it..." Scott begins, "is it dead? What happened?"

Stiles shakes his head – not denial, he honestly has no idea. Scott's nostrils flare, and Stiles wonders, a little helplessly, what an incubus smells like to a werewolf. He watches Scott pace the room, examining everything, then he throws the shutters open and peers out the window. He sniffs at the sill first, then he cranes his head outside.

"Stiles!" he calls, sudden and urgent.

Stiles is quietly glad that whatever Scott's found out there has his full attention, because the mess he makes scrambling out of bed and tripping over himself while _barely_ holding Lydia's nightgown closed over his naked body is not his greatest moment.

"Do you see that?" Scott says, when Stiles joins him.

Stiles peers down, but he doesn't have werewolf vision _or_ the miraculous ability to find a single shred of clothing from his one-true-loveleft on a branch in the woods a mile away, and he has no idea what he's looking for. "What?"

"There! Don't you see it?" Scott turns on his tail and races for the door, leaving Stiles alone, barely clothed, and none the wiser.

_Werewolves_. Jesus.

* * *

He's delayed in joining Scott outside by the need to find himself something to wear that won't leave him exposed and freezing in the early morning wind. His hands are numb and his heart is beating like it isn't counting on ever getting the chance again, and it all takes him far too long.

Scott has left the outside door open in his rush to get down there; Stiles calls his name the moment he's through it.

"Over here!" Scott yells back, and Stiles has to run halfway around the tower to join him.

Lying in the dirt maybe fifty paces from Lydia's window, Scott has found a body. It's a dead incubus, features shrivelled like death aged it a thousand years before leaving it dry; its face twisted in a rictus of agony, the stone around it splattered and stained with an oily black fluid. It must have snowed in the night, leaving its skin dusted a thin layer of white crystals, and the effect is to make it seem almost as though it must have been here much longer than a few measly hours; like they've chanced upon a sculpture left in this spot to commemorate a victory over the forces of evil a hundred years ago.

If so, the sculptor was meticulous in his detail. There's no missing how the membrane of one of its wings has been torn clean through, the remainder hanging from the elbow of the splayed wing like the banner of a fallen army, where it stubbornly refuses to flutter in the wind. Its throat has been ripped out, the wound so deep its whole head cants backwards at an unnatural angle. There's not a freckle of skin paler than an ugly grey anywhere on its body; it looks inhuman and demonic in a way that shares nothing with whatever Stiles experienced last night whatsoever.

He can't even begin to sort out what he's supposed to make of this. Scott, being Scott, has missed this fact entirely.

"It worked!" he exclaims. He sounds awed, ecstatic – like even with Stiles and Lydia both miraculously alive, it's only this that has him convinced of their victory. "Stiles, it worked!"

Stiles stares at the dead incubus and feels sick to his stomach. He doesn't know what to think. He's saved, at least temporarily, from having to make up his mind by the sound of two more sets of boots tramping briskly through the snow, followed by the sight of Lydia hurrying towards them, Jackson trailing puppy-like in her wake.

Her cheeks are flushed a vivid pink, and Stiles is fairly sure the oversized coat she's wrapped in isn't hers, or from the wardrobe of anyone else who ever lived in the upper floors of the tower. He's also fairly sure the hint of cream showing at her neck is the same night dress she was wearing last night when Scott carried her downstairs. The open-mouthed look of horror on her face at the sight of the body has to be a mirror of Stiles' own, except...

Except that it's not, because Stiles has no more hope of understanding what's going through her mind right now than he does anything else about what's happened to them all here – doesn't know how much Jackson or Scott have told her or how much _she_ remembers, or how she's supposed to have any hope of dealing with this when even Stiles can't. And suddenly the fact that he doesn't know feels like the greatest failure of his whole short life; so much it makes his heart ache for her and just about takes his breath away.

Lydia's hands clench into fists at her sides. "Burn it," she commands, her voice hardly shaking. "I want that – _thing_ burned to ash before sundown."

"Is that really necessary?" asks Scott, all kinds of uncertain. "They don't – they don't come back to life, do they?"

For several moments there's silence between all of them, but for the whistle of the wind and the rapid exchange of looks.

"...I'll start collecting firewood," says Scott, looking decidedly spooked as he vanishes away around the curve of the tower foundations.

Lydia turns on her heel and marches back to the tower door. Jackson calls her name and steps towards her, but she sweeps straight past him without a glance. For a few seconds he hangs there, undecided, looking back and forth between her departing form and the body of the incubus lying in the snow, which clearly holds just as much morbid fascination for him as it does for everyone else. Then he throws Stiles one quick, desperate look that might even have been gratitude coming from anyone other than Jackson, and hurries after her.

Suddenly alone, Stiles sinks straight down to the earth beneath him and drops his head onto his knees. Something happened here last night; something he's not nearly ready to process yet – maybe won't ever be – and the understanding of just _what_ hovers around the edge of his perception like a moth around a flame. Only he's the moth in that metaphor somehow, and he has the unsettling feeling he burned up long ago and just hasn't got to realising it yet.

He stays like that until the cold of the snow has soaked straight through the seat of his coat and his muscles have gone numb.

* * *

Stiles comes out of his funk because Scott – once again – has his hand on his shoulder. "Stiles? Are you okay?"

Stiles blinks at him blearily and decides standing up isn't his best choice right now. "No. Yes. I don't know. 'Okay' is possibly not the word I'd have chosen."

"Stiles," Scott looks at what's left of the dead incubus and back again. "Did it... did it hurt you?"

"Not really?" His first instinct is to lie about it, but the real concern in the way Scott's looking at him draws more honesty out of Stiles than he'd intended. "It was like something out of a dream and I don't know how much of what I _think_ I'm remembering even really happened."

Scott gives his shoulder a gentle squeeze. He's never been the sharpest knife in the drawer, but on a good day he still gets when he's _not_ getting something important, and this is one of those days. "You wanna talk about it?"

Stiles shakes his head.

"That's okay, you don't have to," Scott says quickly, then after a moment, sounding a lot less certain, and in a voice that suggests he's trying to reassure both of them, he adds, "You know, messing with your head is what they _do_ , right?"

Stiles takes a long look at the body.

"Oh yeah," he agrees. "That's what they do."

* * *

Building a bonfire large enough to burn the incubus turns into a back-breaking slog of a job that Stiles is terribly, terribly grateful for, considering that no-one much wants to talk about what happened last night, and being left alone with his thoughts any longer would be all kinds of unpleasant. No-one wants to touch the body, not even to move it somewhere more sheltered, so they build themselves a wood pile right over where they found it. The firewood left to their stockpiles this late in the season was never laid down for cremating something the size of a human out in the wind, and the only comfort in being sent out into the woods for more at this time of year is that at least it's too cold to be very damp. That and how they have Scott's wolf-muscles to do the worst of the heavy lifting.

Some days, Stiles is really okay with having wasted most of his sixteenth year helping his best friend get over the urge to murder him every full moon, if this is what he gets to show for it in the long run.

The maid and cook show up later to gape at the slain beast for themselves, once Jackson coaxes them out of the kitchen. Stiles doesn't even remember what he says to them, just the disbelief on their faces and how it becomes one more awkward new reminder that no-one, however much or little they might have been involved, is feeling much like celebrating their victory yet. Jackson tries to help once he's herded them back inside again, but it's pretty obvious his shoulder is still doing its best to drive him to distraction. The only thing keeping him out here is that he's far too stubborn to own up to it whenever Scott or Stiles throw a subtle hint his way that maybe he should go lie down before he passes out. Mostly, he just gets in the way and makes the people doing the real work feel seriously uncomfortable. Less than twenty four hours gone, and already their emergency camaraderie is going sour. How unexpected.

Eventually, the three of them hit on a system – Scott drags and chops the largest pieces from the woods; Stiles carries and stacks the pieces around the body, and Jackson helps. If this mostly means that Jackson spends his time _re_ -stacking Stiles' work a pointed foot or so closer to the body than Stiles has any particular desire to get, then what the hell, he's not complaining and everyone wins.

It takes far too much work and a whole bottle of perfectly good spirits to get the damn pyre to light and stay lit, gradually building into a good-sized blaze under a plume of smoke that funnels up with the wind. They've been pretty lucky the weather has stayed clear this long as it is. Stiles was expecting the incubus's funeral pyre to reek of all the worst things about burnt or rotting flesh rolled into a nauseating stench, but it doesn't smell of anything beyond the tang of damp wood, smoke and heat. Somehow, that's almost worse.

He watches it burn, too tired to censor his own thoughts anymore, or to hold off facing the fact whatever it was that saved them, _nothing_ about his stupid plan had worked. Something happened last night and he doesn't understand what, but he can't tell Scott that because he wouldn't even know how to begin. They're all alive – Lydia's alive – and they're all so relieved that Stiles can't bear to touch that.

Lydia stares into the fire with a haunted look in her eyes until only the blackened bones remain.

* * *

With all the excitement it's almost sunset before they remember it's going to be a full moon tonight.

It's been a year and more since the full moon was a problem for Scott, but with the threat still fresh in his mind, it's no surprise that he's antsy tonight in a way he hasn't been in a long time. Lydia's as close to being his alpha as anything he's ever had, and that thing with how they dealt with the monster without Scott ever getting to lay a paw on it hasn't done much to reassure his inner wolf that the danger is past. Scott-the-human may be happy to sit inside tonight in the spirit of solidarity, keeping Stiles and his nerves company, but Scott-the-wolf wants to go patrol the woods and howl into every shadow to let anything lurking out there know this home is guarded. Within an hour Stiles tells him to just _go_ already, though not without a warning to be careful. The hunters are due back tomorrow and may already be close, and if they find him out there wolfing around they're not going to ask questions first.

Scott vanishes out the door with a last, guilty look over his shoulder, and Stiles makes a spirited attempt at being so exhausted he falls straight into a dead sleep the moment his head hits the pillow.

An hour or two of tossing and turning later, he has to admit his plans aren't showing a very promising trend lately.

The very idea of keeping himself from turning last night's events over in his mind all night is laughable. It's all he's been trying not to do all day. The worst is the feeling that he _should_ be able to piece it all together easily, but the truth remains that Stiles is one or two vital assumptions short of being able to make himself believe any conclusion he comes to. Nothing about this makes sense – starting with there suddenly being incubi in this part of the world at all. Further complications include the futility of trusting anything said, done, demonstrated or even obliquely implied by any member of a race of demon known for messing with your perceptions. He doesn't know how much – if anything – of what he thinks he remembers from last night really happened; not except for the parts that proved how embarrassingly far he is from qualified to understand any part of _anything_ that would explain the mysterious ways of the incubi.

Even if Stiles thinks he's put it together... what if that's just what the incubus wants him to believe?

He's already dreading the conversation he's going to have to have with Deaton next time he's in this part of the country, which is pretty funny when he'd still seriously consider giving up a finger or two if it brought him his mentor tomorrow. Which is already kind of an improvement, because only hours ago he'd have gladly sacrificed a whole foot in return for 'yesterday'.

He could ask the hunters when they make it back tomorrow, he supposes. Incubi are the kind of things they're supposed to know about, even if they don't see a lot of them locally around these parts. After all, there's probably only an even-odds chance the hunters will decide Stiles' story is a sign he's still under the thrall of a malicious being, and will have to have its influence tortured out of him for his own good.

Even incubi only scare Stiles a little bit more than Christopher Argent does, let alone him _and_ the rest of his family (saving only Allison, who was clearly found on a doorstep as a baby; possibly as some sort of heavenly gift entrusted as the saviour of lost souls).

Ordinarily, on a sleepless night, Stiles' refuge is his hand and his imagination, but tonight that's only doomed to lead him into recalling all those other parts of last night that he's been trying so hard not to dwell on. He _should_ have spent the day remembering what the incubus had done to him every time he moved. Every time he rolled his shoulder or moved a hip there should have been the reminder of exactly what sort of strenuous activities the they'd got up to last night. But there's been nothing, until the very _lack_ of awkward reminders proves his undoing and Stile finds himself worrying over the details of the encounter, terrified of losing something crucial before he ever gets close to making sense of it, until he gives up all pretence of maintaining any approximation of scientific detachment. _Had_ there been a bruise when it bit him on the shoulder? Had it really taunted him with the threat of leaving him alone and frustrated mere moments after assuring him his choices were sex-and-death or sex-and-silence? What, exactly, had it been like when it kissed him? Already, it feels like something that happened weeks ago rather than only last night; or maybe a six-month-old fantasy worn long past its best days. Nevermind that after _that_ the inadequacy of his hand is far more than he wants to deal with yet.

Sometime after midnight he finally drops off. He wakes barely an hour later from a vivid nightmare that the incubus is on him, only to see the hunters burst into the room, drag it off the bed and rip out its throat, then toss its body out the window. Before Stiles can decide whether to thank them or curse them and weep, they're dragging him off the bed the same way, and when he tries to tell them they're making a mistake his teeth feel wrong and his mouth won't work, and when he looks down at his hands he sees claws protruding from the ends of shrivelled, blackened fingers.

'Drenched in sweat with a heart beating like a drum' doesn't do justice to the state he's in after waking. Deaton's taught him a few things about the meaning of dreams over the years, but scholarly analysis would be wasted on material like _that_.

Eventually, Stiles gives in to the inevitable. He gets up, lights a candle, retrieves that thrice-damned book of poetry, and sets himself to pour over every line of the poem that got him into this mess for the slightest, subtextual hint of anything he might have missed. When that fails, he goes back over his other sources with the same level of scrutiny.

He's still at it when Scott comes back to find him, shortly before dawn.

* * *

In the morning, Lydia takes to reasserting her authority over her life by ordering them all around like she's not merely queen of the castle, but the queen who's discovered her servants have been slacking off their duties in her absence (nevermind it was an absence of barely twenty-four hours, during which she never technically left the building). Neither Stiles or Scott have ever been very good at taking orders without giving lip, or really gotten used to this lean-times arrangement where they're getting their instructions directly from the lady of the manor. Fortunately, Lydia seems to take their moaning as a sign everything is back to normal. (It's not, and Stiles is a thousand miles away from believing it ever will be, and as a coping strategy what Lydia is doing is as transparent as glass. But when it comes down to it, reminding himself that Lydia probably has it even worse than even he does today is pretty close to being the best working distraction he's got.)

As the hours drag on, there's no sign of the hunters, and no-one's happy about that – least of all Scott.

"You have that look," Stiles tells him, poking Scott with the end of his broom. "It hasn't been twoweekssince you last saw Allison. You can wait a couple of hours longer."

"That's not it," Scott protests.

"Then what? Enlighten me."

Scott gives up on sweeping and leans awkwardly on his own broom handle. "They're still not back. They've been out in the woods in the middle of nowhere all this time. What if Lydia wasn't the first one it went for? What if it got to Allison first?"

"Allison?" This is such pure, classic Scott McCall that Stiles sort of wants to frame it and stick it on a wall somewhere. "The one out in the woods with a whole family of hunters?"

Scott has the decency to look a little bit embarrassed. "We don't know they've ever seen a real incubus before."

"Scott," says Stiles, "I promise you that if our incubus was stupid enough to go after a hunter, we would not be having this conversation because it would be dead and we'd never have known it existed. It would be so dead that what we found in the snow yesterday would look peachy and energetic in comparison."

Scott hunches a little and nods along to Stiles' painfully obvious point. "I guess... if even _we_ managed to take care of it..."

"See? The hunters will be back any time now. So relax and help me with these dust bunnies. Some of them have teeth, I swear." It's not a lie. It's hardly even a lie of omission, and he's telling it to make Scott feel better, so why does it settle in his stomach like a lump of lead?

Luckily for Stiles, this is the moment Lydia chooses to pop her head around the door and save him from what's left of this conversation.

"Stiles," she calls, with an elegant swirl of strawberry hair, "I need you upstairs."

Stiles, naturally, manages to thank her for her timely distraction by blurting out, "What? Why?"

" _Now_ ," Lydia pronounces, and flounces away around the corner.

Stiles shoots Scott a look, but his friend just shrugs at him. Stiles shoves his broom at him and hurries out after her, very nearly running head-first into Rebecca, the maid, in the hallway as she bustles past with her arms full of bedclothes. ("If anyone asks, I burnt these like she told me to and the ones on _my_ bed just look the same," she hisses to him. Stiles holds up his hands and flattens himself against the wall to let her pass. Yeah, no-one's escaping Her Ladyship's rampage today.)

He doesn't know what Lydia wants him for, but assuming Jackson's not waiting for them up there – and that ought to be a safe bet – this will be the first time they've been alone together since she woke up. Does she want to thank him for saving her life? That would be pretty amazing, though also kind of awkward. Lydia's hardly ever given him a second glance until now, but he's never contributed to saving her life before either. He has no way of knowing how likely it is.

Lydia's facing away from the doorway when Stiles peers around it, turned instead to inspect one of her bookshelves. "You... needed me for something?" he calls, and only then notices that the shelf she's looking at is the one where all the remaining books are canted on an angle to fill the gap left when Stiles removed his three historical volumes two nights ago. "Oh... the _books_ – I was going to put them away as soon as I was done, you know, researching what we were dealing with; I guess it slipped my mind with everything. I can got get them right now!" but he's not even turned to go before reality checks in. "Except that if that was all you wanted, you would have told me downstairs and been done with it. So..."

Lydia turns on her heel and gives him one of her many Looks. "Are you quite done?"

"Yes Ma'am."

Lydia leans significantly back against the shelves. "Stiles, I called you up here, because I need _you_ ," she says,"to explain to me what happened last night."

Okay. So he came up here not knowing what to expect, but that is officially not a question Stiles feels prepared for. "Didn't Jackson fill you in already?"

"Just – humour me," says Lydia, with that twitch of her chin she generally saves for dealing with the terminally slow. "You're the man of the hour, aren't you Stiles? I want to hear exactly how you killed the incubus – in your own words."

Stiles takes a deep breath. He can do this. He can probably even do this without – technically – having to lie to her. "One of the books I borrowed mentioned this way you can trap them. Incubi prey on young women – that's what they're built to do – but the idea is if you can trick them into attacking a man they _think_ is a woman, it messes up their magic enough that it weakens them and leaves them vulnerable. You can even kill them that way. So my plan was to – to borrow one of your dresses and put myself in your bed and see if it took the bait. Which it did, and the rest is history."

Lydia listens through his explanation with the expression of someone whose patience is being tried to its limits. When he's done, and has apparently exhausted his window to add anything more, she gives a short sigh and shuts her eyes. "No, you didn't," she pronounces.

"Pardon?"

"No, you didn't," Lydia repeats, "because _that?_ Does. Not. Work. The _myth_ that an incubus finds contact with a human male 'distasteful' derives entirely from a mistranslation of an account originally recorded in Latin over five centuries ago; likely popularised by a class of desperate young men who will stoop to trying to convince the objects of their affections that they'll be miraculously made safe from incubi attacks simply by having a _man_ sharing their beds. In reality, there are _dozens_ of well-documented accounts proving that incubi are just as willing to pursue male victims as female. The _correct_ translation attributes the incubus' defeat to the lethal dose of arsenic its victim was fed before being laid out. When the incubus attempted to drain him of life, the poison reversed the effect and killed the demon instead. His being male had nothing to do with it whatsoever."

Lydia folds her arms and raises her eyebrows at him. Stiles gapes in complete incredulity and more than a little awe. "How do you _know_ that?"

"I _read,_ Stiles," says Lydia. "My Latin tutor felt an understanding of the risks one takes trying to translate the classic texts with a less than perfect appreciation for linguistic nuance was integral to my studies. It's all in _Scriptores Graci et Romani Commentarium Grammaticum_ , which I can't help but notice is also missing from its shelf."

Holy mother of god, thinks Stiles, _why_ did Lydia have to be the one who was unconscious for the whole mess? She and her amazing brain could have saved them so much trouble.

"Now are you going to tell me what really happened," Lydia asks, "or will I have to explain the full nature of your omission to Scott and Jackson – _and_ the Argents the moment they get back?"

Stiles swallows around a lump in his throat the size and texture of a walnut. "Okay, so you're right," he admits, stepping a pace into the room and self-consciously tugging the door behind him mostly-closed. "There _is_ stuff I didn't tell..."

Two seconds worth of sudden and unaccountable vertigo are all the warning Stiles gets before the world blacks out.

* * *

The first thing Stiles notices when he wakes up again is that someone's moved him down to the servants' quarters, laying him out on his own mattress.

The second thing is the incubus is sitting in a chair across the room, watching him with an expression of furious intent.

"Holy god!" It takes the space of an instant for Stiles to go from lying down to halfway out of bed and trying very hard to melt into the wall behind him.

"Hello, Stiles," says the incubus, smiling in a manner Stiles doesn't find all that pleasant. With the useless clarity of a man about to die, Stiles has the impression of something different about it this time. It looks oddly paler in the late afternoon sunlight, leaking in through the window, and not in that appealingly human way that had so captivated him last time either. There's the impression of wiry tension running through its entire posture, from its shoulders to the deceptively casual cross of its legs to the set of its jaw.

" _You_ ," it says, and oh look, now it's not even pretending to smile anymore, "broke our agreement."

"Our _what_?" Apparently this is just how Stiles is going to deal with every confusing statement anyone throws at him today.

"You tried to tell someone about me." The incubus pronounces each word very carefully, clearly hailing from the Lydia-school of dealing with the terminally slow.

"I nev... _oh_." Jesus, this is humiliating. Stiles has spent _how_ long going over everything that happened last night, and the part where the incubus made him promise never to tell anyone – that still slipped his mind? "But that was..." he protests. "I thoughtyou were going to kill me anyway!"

"And since then," replies the incubus, tone dripping with contempt, "nothing's happened – nothing's come to light – to make you wonder if you might want to reassess that."

Stiles takes the opportunity to swallow, self-consciously slow. "Are you... going to kill me now?"

He could have done without the way it relaxes into something like amusement at the idea of Stiles' mortality. "Fortunately, I don't have to. You'd think someone who knew enough to set up that incense would have understood what it means to give your word to one of my kind. But you've found out the hard way by now, haven't you Stiles?" and only then does Stiles get around to thinking back on what it had felt like the moment before he'd passed out.

"That was a – you put me under a _geas_? That's why I passed out back there?"

"You put _yourself_ under a geas," says the incubus. "The moment you accepted my terms."

"So when I was... oh, Jesus." Stiles presses both hands into his forehead. "I am an _idiot_."

The incubus waves a hand. "Do go on."

Magnanimously, Stiles opts to let that comment go. "So, I literally cannot tell anyone about you. If I try, I'm out cold. Okay. Glad we got that cleared up." He glares at the incubus over his fingers. "You know, Lydia's not just going to let this go. I'm going to have to tell her something."

"So you tell her _a lie_."

" _What_ lie? I don't know how much of this you caught through your whole geas deal, but she's not going to fall for just anything, and now she's going to want an explanation for why I passed out too!"

"Not my problem." The incubus gives a casual shrug. Stiles gapes at it.

"Seriously?"

The incubus fixes him with another look. "You think I came back to hand you a cover story? You're going to tell her whatever it is you can make her believe. And you're going to do it because you already know that you only get so many accidental slip-ups before the geas stops letting you off so easily."

Stiles scrubs his hands through his hair. This is what he gets for dealing with incubi; locked in a bind where he has no choice but to wrack his brains for something Lydia will believe when she _already_ knows he's lying to her. Small wonder demons are known for being more trouble than they're worth.

"Why does it matter to you so much that people don't know about you, anyway?" he asks, a little desperately. "Are all the other incubi in town going to think less of you if they find out you let me live?"

The incubus elects to respond to this question by demonstrating that it can, in fact, carry on a whole side of a conversation with nothing more than a string of significant, sardonic looks.

A loud sigh whistles its way through Stiles' lips. "Did you show up just to clear me up on all this? Because I'm pretty sure I would have figured it all out for myself by now if I didn't have you looming at me from the corner over there."

Rather than answer, the incubus stands up, a fascinating process which seems to run through every relevant muscle one by one, then positively stalkstowards him.

"Oh," says Stiles, all the heat in his body rapidly pooling southwards; he'd actually gone and forgotten, somehow, just what effect the incubus's presence had on him. "Again? Here? _Now_?" By the last word it's reached his mattress; Stiles has to crane his head backwards now to look it in the eye. The simple act of breathing is suddenly demanding far more of his concentration than it did a moment ago.

"Did you have other plans?" The incubus places both hands and a good deal of its weight onto either side of Stiles' shoulders in meaningful fashion, leaving Stiles struck anew by the way his whole body sinks with the mattress – even his own thin, crappy mattress on his own thin, crappy bed – beneath its weight.

"No," he says, "Definitely not," and underlines his enthusiasm by shoving the blankets out of the way, distantly pleased that they go easily with no extra struggling. Seems Scott got as far as taking his shoes off and dumping him in bed, but stopped short of tucking him in or... wait, that might be a problem. "Um. Except-for-how-Scott-could-walk-in-here-any-moment," he babbles, "That might not be so good for-"

There's a brief flash of white teeth. "Your friend is taking your collapse after two nights without sleep as a natural sign of exhaustion," the incubus tells him, as it climbs properly onto the bed. "He's making sure everyone leaves you alone long enough to get some real rest."

Stiles quietly retracts every horrible thing he ever said about Scott McCall; looks up at the incubus nervously and swallows again. God, it's all so different in the daylight, now he can see it better. "You _promise_ you're not going to kill me this time?"

The incubus actually rolls its eyes at him. "I'm starting to think it's the only way to stop you _asking_."

"Hey, don't blame me! You guys have a reputation," Stiles protests, holding up his hands.

The incubus raises its eyebrows at him and generally looms. Damn, but it likes _looming_. Stiles likes how it likes looming. This is one incubus that can loom over him any time it likes. "Oh, because you're some kind of friendly incubus who _never_ kills anyone, and I should just be able to tell," he babbles, with what is very little more than false bravado at this point.

The incubus, suddenly, doesn't seem to be making eye contact anymore, and Stiles is just as suddenly aware how terribly he actually doesn't want to know.

"Um," he says, "Can we forget I asked that?"

"Stiles," says the incubus, "shut up," and kisses him.

The kiss is vicious and demanding; the incubus sucks on his tongue like it's mad at him for ever wasting it on other uses (hell, caught in the moment it's beyond Stiles to disagree) but if it was assuming it would be enough to shut his brain down for long, he's going to disappoint it. When it gentles the kiss and begins to pull away from him, he thinks _wow_ , and _I could so get used to more of this_ , and then the words, "You know, if _this_ is what breaking your geas gets me, I'm not feeling a lot of incentive to be more careful," come out of his mouth the moment he has use of it again.

The incubus makes an exasperated noise and leans back to look him in the eye. "Too bad. From now on, you break it, you wake up alone." It jerks its head for emphasis. "This isn't going to happen again."

It's slightly possible this last declaration leaves Stiles even colder than the idea he's possibly sleeping with a murderer, which is so much more than he's going to let himself analyse any time soon. Somewhere during this kiss he must have reached for it, because his hands are clutching at the incubus' sides, and he's tightening his fingers to hold it here before he knows what he's doing. "Why not?" One kiss, and he's back to _pleading_.

"What exactly do you think this is, Stiles?" The incubus is definitely losing patience with him, though it pairs this with a shimmery sort of movement that sends muscle flexing under Stiles' hands. _You can't hold me here_ , it's saying, but all it does is make Stiles desperate to know how that would feel with his lips where his fingers are now.

"Okay, okay, let me rephrase _,_ " he says, mind racing and far too much of his attention wasted on the feel of the incubus' ribs under his thumbs. "So why _now?_ "

This seems to go over better. Stiles gets maybe half a second to take in the wicked glint in the incubus' eyes before eye contact is gone because it's doing that amazing thing where it puts its mouth right up against the side of his neck and just _breathes_ into his skin, warm and wet. Right under his ear, it tells him, "I was _hungry_ ," and closes its mouth over the skin below his ear. Stiles moans.

The slide of the incubus' lips working their way below his jaw is the _best_ kind of distraction; it takes another half a minute or so for Stiles to even remember that there are still things he needsto know he understands here. "For... you mean for life force? Are you sure this isn't going to hurt me?"

The incubus is abruptly _not_ sucking kisses into his neck anymore. "Stiles, either I kill you or I don't. There's no halfway. Happy?"

"Then why don't all... wait, waaaait, I get it – that's _why_ you're still hungry, isn't it? It's _because_ you didn't kill me. Whatever it is you get from us, you don't get as much if we're not dead at the end." Stiles grins, intensely pleased with this deduction.

The incubus glares at him. "You realise there are less difficult people I could go to for this."

"No, _no_! I'll shut up, I prom- no, wait, I still have to ask you something!" In a frustrated jerk of motion the incubus makes as though to leave the bed altogether. Horrified, Stiles grabs it by the upper arm and holds on. "No, don't, it's important! That other incubus, the one that attacked Lydia – _you're_ the one that killed it!"

The nuance of the incubus's glare seems to be saying, _please tell me you didn't only just figure that out now_.

"Yeah, so that was pretty obvious. I just – _why_?" Even if it does cost him his second chance at sex, he needsthis much before he goes mad wondering. "It wasn't for me; you didn't even know who you were going to find in there. So why?"

"Maybe he was muscling in on my territory," suggests the incubus, testily.

" _Your_ territory?" Stiles coughs out half a laugh. "We don't have incubi out here! There hasn't been an incubus seen this far west in – in _ever_. Suddenly there's _two_ outside the same window in the same night?"

The incubus is close enough that when it gives an impatient huff, Stiles feels it against his skin. " _Yes_ , Stiles." It sounds _furious_ now, "Suddenly there's two, and _one_ of them is leaving bodies lying around in their bedrooms – letting himself be _seen_ by people who aren't even his prey, just to toy with them – and leaving his prey enthralled and unconscious for a _whole day_. Like he _wants_ every hunter within a hundred miles turning the country upside down to find him and every last one of us out there besides!"

Hearing it that angry should be terrifying, except that for the first time today, Stiles has a pretty good idea that what's upset it doesn't have anything to do with him.

It occurs to him all in a rush to wonder how people are supposed to knowthere aren't any incubi in a place where they don't leave bodies behind – when even _he'd_ woken up the morning after convinced the whole thing had been a dream. His hand is still resting on its bicep, not gripping anymore, and he stares dumbly at it for moment, wondering anew that it's even real. "Oh. _Oh_. Then you were – you've been... how long have you...?"

"How long have I what? Lived here? Been tracking him?" The incubus resettles itself in a manner that, to Stiles relief, no longer suggests it's three seconds from giving up and leaving. Its voice deepens to a low hiss. "Let's say _long enough_."

"You saved my life that night," Stiles breathes, and maybe for the first time he really believes it too. "We'd all be dead if you hadn't..."

This gets him a satisfied smirk. "Feeling grateful?" it asks, and for once Stiles is lost for words. He should be _dead_ but instead he gets _this_ – it doesn't make any sense, and the only answer he can come up with is to get a hand up behind its head and tug it down so it can lick its way into his mouth again, slow and wet.

" _That's_ the idea," it murmurs, once it has Stiles so out of breath he has to come up for air or suffocate. It's on him again before he's even done panting, leaving him light-headed and giddy; the only thoughts left in his head the ones that go _yes_ and _I should have_ died _, how am I so lucky?_ This is maybe not the best time he could have chosen to face just how close he came that night, but there've got to be worse ways to spend the rush of adrenalin and relief. For just now, it's no effort to forgive the incubus for beingan incubus – he can even forgive it for being a sardonic asshole who's only here to use him for sex. Stiles is feeling more grateful than he has any idea what to do with if he can't share it.

The next thing to matter enough to pull him back down to earth is the incubus working on the belt around his tunic, then tugging him up so Stiles can help rid himself of the rest of it. It slides down his body to tug his pants down and away, and the little space and air that puts between them turns out to be exactly the perspective Stiles needs to find himself newly rapt by how it moves, developing a whole new appreciation for the way the light plays over its weird mottled skin. He needs to go back to Deaton's anatomy lessons and learn the _names_ of all those muscles. Who caresif it's mostly _thrall_ speaking right now or whatever; who could ask for a better way to celebrate being alive?

"Do you have a name? I mean, you don't have to tell me," he amends, quickly, when the incubus gives him another one of its looks. "I know how that can be bad news. But if there's something I can call you, I could, you know, call you that. While we do this. If you like."

The incubus freezes, like Stiles has it trapped in his gaze, and for a long moment he can't begin to guess what it must be thinking. He itches to touch again, but it's sitting just out of easy reach. If all he's going to get for his trouble is a snide refusal, he wishes it would put him out of his misery already.

"Call me Derek." The name comes out in an almost-growl, and it takes Stiles a moment too long to understand.

"Derek?" Stiles echoes. "You want me to call an incubus ' _Derek'_?"

Derek-the-incubus gives him another one of those looks. "You _asked_. No-one's forcing you to use it."

"Yeah, but..." Several questions die on Stiles' lips as he watches the-incubus-who-may-or-may-not-answer-to- _Derek_ lower its nose to his chest and rub its cheek into the skin around his naval – luxuriating in it, almost – before trailing down further, dipping into the crease of Stiles' hip. Stiles has barely time to think _what is he doing_ before what he's doing turns into mouthing the base of Stiles' cock with a look of utter contentment.

The noise Stiles makes is hardly a moan, it's almost a _squeak_.

The incubus flicks another one of those wicked looks up at him and Stiles' breath catches – he'd been so ready to see mockery after that noise he just made, and there's nothing like it there at _all –_ but that's officially all the reprieve he gets before the incredible slick heat of the incubus' mouth is back again. Stiles can only stare, completely fascinated, as Derek drags up his length to mouth the head, tongue dragging against the foreskin in a way that makes it very, very hard to sit still. This is lewd in ways he can't begin to deal with; he's on his back on his bed in the room he used to share with six other people and that he _still_ shares with Scott; there's sunlight coming in through the window; and he's neverin his life felt this naked. There's a _demon_ that looks like a human to Stiles in all the ways that matter to him and none of the ways that don't, with its _mouth_ on a part of him the town rectors always told him he's not supposed to even _touch_ more than he absolutely has to – looking like it's never tasted anything better in its life. _He_. Like _he's_ never enjoyed anything so much before in _his_ life. He just gave Stiles aname, and even if Stiles can't quite make himself think of an incubus as 'Derek', there's no way you can think of a Derek as an it.

Stiles is trying so hard not to move, partly because he thinks he's not supposed to, but mostly because he knows the moment he does – arches into this or thrusts – he'll lose what little clarity he has left and it'll all be over so much sooner. He feels himself bump against the back of its throat and somehow he keeps _going_ , the incubus swallowing around him, and that has to be wrong, how is that even _possible_ to be that far inside and it's like it's urging him to thrust even _deeper_ , is this something regular humans can even _do_? God, _Derek_ – Derek goes right on swallowing around him the whole time he comes.

It's a little confusing, at first, for Stiles to find himself awake afterwards, once he's back to where he can do confused again, but definitely the good kind of surprised, even if 'awake' is officially the most effort he's going to be up to for a little while. Derek is licking his lips and looking terribly pleased with himself. "Sounds like you've got the hang of it to me."

Belatedly, Stiles remembers having yelled that name at least a couple of times towards the climax of events back there. There may have also been some begging. Whatever – he's gracious enough to let _Derek_ have that one uncontested.

"Oh good," he says, distantly, "whadya wanna do now?"

Derek exhibits no hurry whatsoever in crawling back up the bed to kiss Stiles again, languid and slow. There's a new taste in his mouth that Stiles would probably hate under any other circumstances, but right now, knowing where it came from, he can't get enough of it, even... Jesus, he can't be getting hard again already, it hasn't hardly been sixty _seconds_.

"Roll over," says Derek.

"Huh?"

"That's what we're doing now," Derek's thumbs trace the skin around his naval in a distracting manner. "But it's going to be a little different this time." Stiles definitely doesn't bother to resist as Derek guides him to roll onto his stomach, then tugs him up onto his hands and knees. They're still shaky and shouldn't be up to taking his weight, except that if he lets his posture dip even a little he might lose that telltale press of warm skin against his back and between his thighs, the awareness of Derek's body over him that's the only sense he's got left, heightened even further now Stiles can't see what Derek's doing.

As usual – and seriously, this is becoming a theme for them – Derek's in no hurry. He takes his time to settle himself; to wrap an arm around Stiles' shoulders and drag his hand slowly over the most sensitive parts of Stiles' neck as he mouths the bumps of Stiles' spine just below his hairline. Derek's cock is resting between the cheeks of Stiles' ass, but he's not doing anything with it, not unless you count casually driving Stiles slightly insane. He feels Derek sigh against his skin, and say, "Did you ever wonder if I'd have still climbed through that window if I'd known it was you in that room? If you'd been there and if Lydia was in the next, who would I have gone for?"

"You didn't seem all that disappointed," Stiles grumbles. He'd swear to god he'd hardly thought about that one in more than passing, so it irks him immensely that Derek is technically right.

"Which do you want it to be, Stiles?" The words make Stiles shiver. Derek has his hands on his ass, running the pads of its thumbs down the inside of his cheeks, so close and so far from where he wants them. "Do you want this to be what you earned by putting yourself in her place – the reward for your useless bravery – or do you want to hear that I'd have gone to you with all the tower to choose from?"

The question makes no sense. Stiles didn't want this until he had it, and now he has it he wants it both ways and neither, any way he can have it. He doesn't want to know; he doesn't want to ask and get an answer he doesn't like. "Haven't exactly been losing sleep over it," he says, caring how steady his voice is.

"No," Derek muses, thoughtful, "I think the one that's going to stay with you is, _will it ever be like this again?_ Will there ever be another man, or even a woman, for you anywhere who can give you what I can?" Stiles starts to pant. He can feel Derek moving, lining them up, spreading his thighs. Good thing he got all that extra air in early; when Derek starts to push inside Stiles doesn't breathe at all until he's done. He starts to thrust, steadily, and Stiles lets out a sob. He can't believe he's come once already. "I promise you, Stiles," Derek whispers, "there _won't_ be."

Something inside Stiles clenches tight; his heart, maybe. He wonders if Derek can feel that, wrapped up in Stiles the way he is right now, but if so it doesn't seem to bother him. In the moment it's way too easy to believe Derek's promise will be the truth.

"Every time, it'll be different – with every person, it'll be different – and _every time_ , you'll remember it's not me," Derek whispers in his ear. He curls his hand around Stiles' cock, not moving it yet, just holding, and the sensation is already next to overwhelming. This is waves of pleasure breaking over a baseline of awe almost too intense to bear. Derek is inside him and over him, a solid presence holding the whole rest of the world at bay. For all those awful promises, all Stiles can think is, _how could it ever be like this for_ you _either?_ and if that sounds foolish even within the confines of his own head, incubi don't come _back_ to just anyone, do they? What does that even _mean_? He knows there's so much Derek's not telling him and he wants all of it. Even if he doesn't know what this _is_ between them, Stiles can't think of this as the end; knows already he won't be able to face that until the bed's long cold without him.

" _Derek_ ," Stiles moans, and Derek drives into him hard, so Stiles says it again. Derek responds the same way, and it turns into a rhythm for them, all the way until Stiles feels Derek tense up and come inside him with a hiss.

He definitely comes with Derek's name on his lips; remembers a hand resting soft against his belly after, easing him down and rolling him to his side before leaving him there to sleep.


	3. Chapter 3

Waking once again well rested and remarkably ache free (and secure in his confidence that this one wasn't a dream either only because he's lost a good half a day otherwise), Stiles seeks Lydia out himself first thing the next morning, before he can lose his nerve. 

"You were right," he tells her. "What I told you – what I told Scott and Jackson – it wasn't the whole story. It's just that Scott was already so nervous about me offering myself up as bait that if I told him I was going to be drinking poison as well, he would've lost it." He knows he's fidgeting and he's not even trying not to, because it was only yesterday Lydia caught him in a massive lie and he fainted in front of her like a little girl. It's perfectly natural that he'd be nervous now. (It certainly doesn't have to mean he's about to tell her an even bigger lie. It'd be more suspicious if he _wasn't_ fidgeting.) "I knew this was our one chance, but there were so many things that could have gone wrong, you know? The dosage, the timing, it all has to be so specific or it doesn't work and I'm dead and the incubus just steps right over my body and it's all for nothing. I didn't want to worry Scott any more than he was worrying already." He shrugs and makes a good attempt at looking properly contrite.

"Right," says Lydia, "Good." She's had this spooked look on her face since Stiles walked in and launched head-first into his new story before he could lose his nerve, but being Lydia, she's recovered again before Stiles can quite make up his mind whether it's a bad sign. "I'm glad we had this talk. Was that so hard?"

Stiles hesitates. "Please don't tell Scott. I don't think he'd take it well. Or Jackson – he'd just tell Scott and-"

"Oh, _Stiles_ ," Lydia croons, "you can count on me. But in future, I hope you'll remember that I expect complete honesty from _everyone_ in the tower. Won't you?"

"A-absolutely," says Stiles, wincing over the stutter. 

"Good," says Lydia again. "Are you feeling better today?"

"Better? Oh, because of how I..." collapsed on the floor in front of you last time we tried to talk about this. "Yeah, great! Nothing a good night's sleep couldn't fix. Nothing big."

"Good," says Lydia, in a voice that's starting to creep Stiles out maybe just a tiny little bit, "That will be all, Stiles."

Stiles bobs through a nod and hurries out, only fumbling with the door latch for a second or two longer than usual. 

Well, that went well. Wasn't so hard, nothing suspicious leftover whatsoever. 

What are the odds someone like Lydiawould have been able to spot the tell tale signs of a geas of silence at work anyway?

* * *

The hunters finally make it back a whole day and night after the full moon, which is only ironic if you remembered that thing where them being back on schedule had been a crucial assumption in Stiles' plans a few iterations back, and only hilarious if you were keeping track of all the other ways his plans had gone hopelessly, harmlessly wrong since this began. Stiles decides he's within his rights to set about blaming them for all of it. 

At least he's not alone in being bothered by the delay. Stiles almost literally has to hold Scott back from charging out into the woods to meet the hunters the moment he catches their scent. When he sees Allison at last, his whole posture sags with relief. Stiles tugs him away from the window and makes him wander down to meet them in the courtyard at a pace that suggests he _hadn't_ smelt them coming on the wind a mile away. 

Downstairs, the Argents and their small entourage of assistants are dismounting, all persons, limbs, hounds and horses present and accounted for. Scott hovers with the awkwardness of a mostly-former stableboy looking at the only horses anyone's stabled here in months, knowing he'll likely lose a finger if he so much as touches any of them. At least hovering around the horses beats projecting the awkwardness of a lowly-(ex)-stableboy who knows he's liable to lose _both_ hands if he's caught laying anything on the Argents' daughter – who herself is being probably a little too obvious about how she's not making eye contact with Scott out here where her father might see. The Argents have their reputation, and they take the care of their own deadly seriously. All the same, it's beyond them to keep their hounds from bounding up to Scott to say hello, tails wagging, which will never not be hilarious. Scott's damn lucky the Argents' dogs liked him long before the day he first came home smelling of wolf, or he'd have been in real trouble.

Stiles sticks to loitering in a manner the Argents can interpret as an offer to help if they like, or just ignore, if that's what they prefer. He likes to think that not being noticed is at least half of any good servant's job description.

Jackson, on the other hand, hardly waits for the riders to come to a complete stop before giving them a piece of his mind. "You want to explain what happened to 'back the morning after the full moon'?" 

Unluckily for Jackson, Kate Argent is the only one paying any attention to him. "Oh, _Jackson_ ," she croons, "You know we missed you too." Jackson dodges jerkily away from what was likely an attempt to pinch his cheek, then does his best to ignore her as completely as Chris is ignoring him. 

"You have _no idea_ what we've been through while you've been out, do you?" says Jackson, sneering through every pore. "Doing what, picking off a were-puppy or two?" Stiles watches Scott wince. "Chasing animals in the woods?" 

"Hunting an incubus?" Kate provides. 

Jackson freezes. "What?"

"You what?" echoes Scott. Stiles experiences a sudden chill. 

"An incubus," repeats Chris, busy unloading his gear and only eventually getting around looking in Jackson's direction. "It went for Kate while she was on watch one night."

"It was kind of flattering, actually," says Kate, thoughtfully. "But I'm thinking it didn't _quite_ count on how much bang it would be getting out of its little late-night snack."

"My sister wounded it – not badly enough, it still got away," Chris explains, or possibly translates. "We extended our trip by an extra night in hope we could track it down, but they don't leave much of a trail. We're back to regroup and pick up new supplies before we set out again."

"Oh. Well, in that case I've got some good news for you," says Jackson. "Your incubus is _dead_."

Jackson finally has both Argents' full attention. 

"What?" Kate laughs. "How would _you_ know?"

"Because we're the ones that killed it." Jackson folds his arms (which doescommunicate a good deal of bravado if you know enough to spot the abortive wince-and-jerk when he reminds himself how much his shoulder still hates him). There's basically zero chance now that he's going to bother to mention he spent most of the ordeal scared stupid and useless and his greatest contribution involved restacking a little firewood. "Yeah, that's right. _Us_ , while all you _professionals_ were congratulating yourselves for letting it get away."

"It's true," Scott puts in, before things can get ugly. "It went for Lydia a couple of nights ago, but we scared it off and when it came back... look, what you need to know is it's dead, and _yes_ , we're sure – we found the body and everything."

The older two Argents exchange a glance. 

"Show me," says Chris.

* * *

There's only bones left to show, but they're plenty enough to convince the hunters that whatever the boys had killed the other night, it had wings and it wasn't human. For once even Chris is dutifully impressed. Kate seems almost disappointed. 

"You'd think they'd know better," she comments, holding up the blackened skull so she can examine it from every angle. "First you underestimated me, then you underestimated a bunch of little boys. That's one embarrassing way to go."

"Hey!" says Stiles, though she ignores him and he's not sure how he was planning on defending himself anyway. 

"Impressive work," says Chris. "I suppose this goes to show even a demon can be taken by surprise."

"That wasn't exactly..." Scott starts. He's never at his most eloquent when Chris Argent is involved. 

"Tell me," says Chris, with an encouraging gesture. "I want to hear the whole story."

Stiles watches Scott panic momentarily. An hour ago, he'd pulled both Scott and Jackson aside and made them both promise not to tell the Argents the specifics of his plan to take down the incubus. He'd let them believe this stemmed from a desire to gloss over some of the more incriminating details, like how it all took place in Lydia's bed while Stiles was wearing one of Lydia's nightgowns and, fortunately, even Jackson had agreed without much more than a bit of pointed smirking. Now Scott has to tell Chris this tale without mentioning either too much about Stiles _or_ the role a werewolf played in scaring the incubus away the first time. It doesn't help that Chris acts like he's interrogating you as a murder suspect _all the time_ , including when all he's asking is whether you could find it in yourself to pass the salt.

"It showed up in Lydia's bedroom a couple of nights ago," says Scott. "Me and Jackson were lucky enough to hear and we chased it away, but it left Lydia in a coma and Stiles said that meant it was going to be back for her, and it wouldn't be so easy to chase off a second time. We came up with a – with a couple of plans to take it down and one of them worked-"

"Mine, in case you were wondering," Stiles puts in.

"-and you should probably talk to Stiles about that part," says Scott, sounding grateful. "Next morning, Lydia woke up and we found it dead. She wanted us to burn the body, so-"

"Wait up," Kate interrupts, suddenly interested. "You only burned it thismorning? The bones are already cold."

"No, it was a couple of days ago," says Scott, looking lost. 

"How many days ago?" asks Kate. 

"Um, it was the day before yesterday. Night before the full moon, right?" He looks at Stiles for confirmation; Stiles shrugs back. 

"Scott," says Chris, in that perfect Argent tone, "You need to be very sure. You found the incubus dead the day _before_ the full moon?"

"Yes?" says Scott. "That's when it was, right Stiles?"

"Night before the full moon," Stiles agrees. "Why? Does that matter?"

"Kate was attacked by the incubus on the night _of_ the full moon," says Chris. 

" _What_?!" Scott exclaims. "But it was dead by then!"

"Exactly," says Chris. 

"But – how?" asks Scott, bewildered. "We burned the body – it was definitely dead! How's that possible?"

"It means there's two of them." The words are out of Stiles' mouth before he can help himself. Chris nods towards him, approving. Go Stiles, first on call whenever your needs include basic mathematics. 

"If what you're telling us is true," says Chris, clearly leaving open the possibility that both Scott and Stiles are merely very confused about what day it is, "that's our only explanation. We've got more than one incubus on our hands."

"Well," says Kate, bumping her shoulder against her brother's, "sounds like there's some work left for us professionals after all, hey Chris?"

Stiles mumbles something about how if anyone needs him he'll be inside, sitting somewhere quiet, and flees.

* * *

He's hardly back to his room before there's a knock at the door that turns out to be Allison. This is great, because he'll take any distraction today, and terrible, because the kind of distractions afforded by getting involved in the inimitable Scott-Allison situation are a kind he often ends up regretting. 

"If you're looking for Scott, he's outside," he tells her.

"I wasn't looking for Scott." Allison closes the door behind her. The look on her face is nervous, possibly even furtive, which is nothing terribly new.

"Did you see him yet? Because if not, your dad is kinda tied up with the whole incubus thing right now, so this could be your chance-"

Allison shakes her head. "I wanted to talk to you first."

Stiles lets out a sigh. "Why does that worry me?"

"Stiles," says Allison, "I killed a werewolf. On the night of the full moon." She pauses and takes a deep breath, eyes fluttering away and back again. "He would have been about Scott's age."

Stiles exhales sharply and slumps down onto the nearest convenient surface, both for his own benefit and as a subtle invitation for her to do the same if she needs to, not that she takes it. "Okay. So that's officially awkward." Heaven forbid the hunters make it home with _only_ the ongoing drama of an incubus or two to show for it. "What happened?"

"He roared at me, and the next thing I knew there was an arrow through his eye," says Allison. "He was dead before I reached the body."

Stiles nods, a little absently. "Okay. Well. Look at it logically: he was about to leap at you, right? It's not like he gave you any reason to think he could be talked down."

"Of course not," says Allison; there's a bitterness in her tone Stiles can practically taste. "It's not like I was a hunter, out there _hunting_ him or the rest of his pack – on the _one_ day of the month when it's hardest for them to hide – with a quiver full of arrows tipped with wolfsbane. Why would he have assumed the worst?"

"Are you sure you don't want to sit down?" asks Stiles. Allison shakes her head at him and continues pacing. " _Allison_. You know they're not all like Scott, right? Most of them never learn control, or they're with an Alpha who wouldn't let them if they tried."

"You think that's _not_ what my family tells me every time we go out?"

Stiles gets back to his feet and puts a hand on her shoulder. "Look, I'm just saying, you don't need to..."

"I _know_ ," she says, "I know – I've done this before. But this is the first time I ever had to face one that looked _that much_ like Scott. I didn't think, I just reacted, and it was over before I even _knew_."

Stiles doesn't know what to do besides hug her, so he does. After a moment she hugs him back, tightly at first, before some of the tension bleeds out of her again. Stiles will call that a win. 

"It's okay," Allison says after a bit, pulling away. "It's part of the plan, right? I need to make them respect me as a hunter who can do this the hard way before I have any hope of making them understand about Scott. I'm sorry to pounce on you with this, I just needed to tell someone who'd understand before I have to face Scott again."

"You should tell Scott. He'd understand." He'll also definitely know she's hiding something if she doesn't, but Stiles isn't going to lean on that argument if he doesn't have to. 

"What he'll understand is I would have been in danger if I hadn't shot first."

"Well, yeah," Stiles agrees. "He's maybe a little invested in your welfare. Doesn't mean he's wrong. He'll get it, just give him a chance to."

Allison nods at last. "Thank you."

Stiles shrugs and smiles back. "So the other Argents didn't have much to say about your big moment?"

Allison shakes her head. "Not after they heard about the incubus."

"Right. Of course not." That's when the next round of implications hit him. "Hey, when it attacked Kate, did you see anything?"

Allison shakes her head again. "I didn't get back until after."

Small mercies. "Did she... say much about it?"

"Just that if only she'd aimed a few inches to the left she would have had it," Allison shrugs. "And that she was looking forward to seeing it again. Then she made some sort of joke about whether it was just the thrall talking. No-one really laughed."

It is a bad, bad day when one discovers Kate Argent has been stealing your material. Bitch. "So she didn't seem all that worried, huh?"

Allison gives him a strained smile. "You know Kate."

Unfortunately, Stiles does.

* * *

Stiles hears the lively debate going on between Lydia and the hunters in the main hall long before he gets close. It doesn't seem like she's taking the news of there being a second incubus at large all that well. The argument is centred around the relative importance of their duties to stay and defend the tower versus tracking and finding the monster, versus hers to supply and support them while leaving the decisions to the Argents. What Your Father Would Have Done goes up against Do You Realise You Left Me Completely Undefended Here? – and then it gets personal. It's riveting stuff for all of the five minutes it takes Stiles to realise that he's already heard more about this subject than he can deal with today, and has to go to find something very important to do somewhere far away. 

He runs into Scott in the hallway, who perks up immediately at the sight of him and hurries over. "Hey, have you seen Allison?"

Stiles points him downstairs and does his very best to avoid the urge to bash his head in against the nearest wall.

* * *

"If I asked you to punch me in the face right now," he asks Jackson, later, "would you take it the wrong way? Understand, it's got to be one that lays me out long enough that I don't have to wake up again until this day is _over_."

Jackson stops hacking at his practice-dummy long enough to catch his breath and say, "We've got a whole tower full of Argents, Stilinski. Get one of them to do it. Isn't that what they do?"

And okay, the Argents may not be Stiles' favourite people right now – or really ever – and they may even be more than half the reason Stiles is longing for a prolonged blackout to begin with – but that's a little more vehemence than even he would have gone for so fast. "Whoa, sensing a little hostility there."

"How the _fuck_ do they expect us to believe there's _another_ incubus out there?" Jackson snarls. "Is this some power thing where they just can't admit how we got all the work done for them?"

"I love this 'we' thing you keep doing when you talk about how the incubus went down," says Stiles, but he's running on automatic – his heart's not really in it. 

Jackson hurls his practice sword down and whirls around. "They got the days wrong." He'd sound almost reasonable if you had zero context and didn't know him all. "It's the only explanation."

"Sure, I bet the hunters get confused about which day the full moon is all the time." Stiles feels as though he's lost control of this conversation much faster than he'd counted on. 

"Then Kate _lied_. She's the only one who _saw_ this other incubus, don't you find that a bit suspicious?"

"Well. Um," says Stiles. 

"I bet she didn't just stab it and let it go, I bet she _summoned_ the fucking thing in the first place. She probably _enjoyed_ it."

"Whoa, hey. Okay, Kate's a creep, this is not under debate, but don't you think you're going a little far?" He's not exactly sure why it ever seemed like a good idea to go vent at Jackson in the first place, but he's pretty sure the idea didn't include discovering that Jackson has even more bottled up than he does right now.

"What would you know, Stiles?" says Jackson, throwing an arm towards him in a jerky movement. "Actually, what _do_ you know? Aren't you the incubus expert around here now? You didn't think to mention they fly around in pairs?"

The image of a pair of identical Dereks coming through his window flickers unhelpfully through Stiles' brain. "I didn't think to mention it because nothing in any source we've got says anything about incubi flying around in pairs. News to me too, Jackson."

"That's _real_ reassuring, Stiles. I'll bet that means they haven't got a single other surprise in store for us. I bet Lydia's going to sleep in her bed tonight feeling perfectly safe."

Stiles rubs his head with both hands. "It doesn't have to be as bad as you're making it."

"Doesn't it? We just _killed_ one of these things, and Kate just pissed the other one off. How would _you_ call the odds it's not going to be back for revenge?"

Stiles makes a really solid effort to stand his ground with minimum awkward fidgeting. "Okay, I may not be an expert. But I'm pretty sure I know enough to say that's not how they operate."

"And why not?"

"Because if there were two," says Stiles, "then I don't think they would have been friendly. They're probably only here because of some sort of messed up territorial dispute or something. If one of them's dead, we probably did the other one a favour."

"Uh-huh." Skepticism drips from Jackson's every pore. "And just how does an incubus express its gratitude to people like us, you tell me that, Stiles?"

"That's not the point, Jackson." Stiles takes a deep breath. "The point is, we killed one incubus, and the other one knows the hunters are going to be looking for it. If it has any sense, it's putting as much space as possible between itself and us right now. We're probably not going to even see it again." The irony that Stiles is trying convince someone _else_ of all this isn't lost on him. 

"Oh," says Jackson, unconvinced, "and if it shows up here again, like every hunter in the tower thinks it will, is that what you're planning on telling it?"

"No, I was thinking I'd try telling it how lousy Lydia is in bed." By the time the words are out there, it's too late to realise how much better they'd sounded in his head. 

Jackson looks at him like he's completely lost his mind, laughs, shakes his head, then grabs his sword back off the floor and goes back to hacking at his practice dummy like Stiles isn't even there. Apparently he's not even worth a comeback at this point. 

Fine, _be_ that way.

* * *

The trouble with Jackson is that just occasionally, under his smug asshole exterior, and under a good half dozen layers of shamelessly self-important, over-achieving interior as well, he still manages to be right about something. If what Stiles heard of Lydia's conversation with the Argents earlier wasn't already enough to clue him in, Jackson's one-right-something for today is how Lydia must be feeling after hearing there's a _second_ incubus on the prowl only two days after her narrow escape from the first one, under circumstances she's justifiably suspicious about already. As the young, beautiful, virginal lady of the tower, any village idiot could have picked her as prime incubus-bait even before the first incubus showed up on her window sill. She has every good reason to be afraid. 

Stiles has known Lydia as long as he's worked here and she thrives on exceeding every expectation held against her. She's always believed somewhere deep down that she ought to be able to run this tower on a cult of personality alone. She hates feeling helpless – it's a thing, and Stiles can relate. Even if he can't tell her the truth, it's his obligation to tell her _something_ that will ease her mind a little. 

This is why Stiles has now spent what must be at least a good half hour lurking in the hallway of the floor below Lydia's bedroom, trying to think of a way to tell her that he's almost positive that the other incubus is gone – and if it's not, then it's not going to go after her – and even if it does, it's probably not going to kill her or anything, so she should really relax. Since his source for most of this information _is_ the incubus and his best excuse for trusting it is that he can't _think_ of anything it would have to gain by lying to him, he's not sure that's going to go down so well. Doesn't help that he's pretty sure Lydia already knows far more about incubi than he does. In the _non-_ biblical sense, at least. 

It's also not much help that even if you ignore the near-disaster that led to his first encounter with Derek, Stiles' greatest hit at predicting demonic behaviour was that thing where he assured Scott no incubus would be stupid enough to attack a hunter. Not that he was wrong about it being stupid (thank you very much Miss Kate Argent for proving that so definitively), it's just the approximate preservation instincts of your average incubus he's apparently let himself overestimate. 

God, who is he even kidding by pretending he has the first idea how this stuff works?

Alright, no sense overcomplicating all this more than he has to, or he'll be standing here all night. The best plans are simple. What he needs to do is walk in there and open by asking her what the hunters told her about whether the other incubus will be coming back, then improvise his way from there. The geas will _probably_ let him get away with making some sort of reference to things the incubus which attacked _him_ said to him before it (ahem) died. He can probably even get away with saying it as good as told him it wasn't the only incubus out here, but it made it pretty clear the other one wasn't so neighbourly as to have much interest in picking up its unfinished business now it has the area to itself. 

Okay. That could work. It'll mean he's being as honest as he'd want to be even without geas-related complications, but he'll still be able to let her know that, speaking as the person with the most first-hand incubi experience in the tower, he doesn't _think_ she has anything to worry about. 

Course decided, Stiles makes for the staircase. He's been loitering in the dark for a good twenty minutes now, ever since he heard someone else on the stairs, panicked, and blew out his candle before he could get caught lurking around in a usually-deserted part of the tower like the indecisive coward that he is, but he's been living here for so many years that it's hardly like he needs more than a hand on the wall and a good memory for where the first step in the staircase will show up to make it up one floor. Once he's reached the upper floor there's a sharp corner between the staircase and Lydia's chambers, but as soon as he's around it the light pooling out through her doorway is right there to guide him. Her door's half open; from here he can already make out the shape of her bed in the candlelight, Lydia herself perched on top of it – sort of awkwardly though, like there's something else on the bed messing up the shapes... 

He hasn't taken another step before it hits him that she's not alone. 

With his heart in his mouth, Stiles realises that's _Jackson_ on the bed with her, laid out on his back on the same mattress Stiles lost his virginity on not seventy two hours before. Lydia is in bed with _Jackson_ , and the way she's moving over his body doesn't leave a whole lot of room for misinterpretation of exactly what Stiles has stumbled into. 

For the first time in his life, Stiles finds himself wishing he could have been born a little lesstalented at recognising people he hates from a sliver of a glimpse through an open door where he can't even quite see a face. God, _why_ did he ever think it was a good idea to spend so much time watching the knights-at-training at work until he could recognise any of them from a side-view of a naked chest and a shoulder? _Why_ did it never occur to him that he'd one day be seeing Jackson naked in Lydia's bed, or how much he'd give for any right to pretend to himself he didn't know exactly who he was seeing?

Lydia's notnaked, but all she's wearing is a shift so thin and tiny it makes that lacy nightdress Stiles borrowed look positively covering. She looks beautiful, and fragile, and completely rapt in what she's doing. ( _Jackson_.) Stiles knows he should leave – the odds of him being seen out here in the dark may be remote, but there's no way they meant to leave the door open for anyone to see – but he can't quite get his legs to listen to him. 

How could she choose _Jackson?_

In all the years he's been lugging around his torch for Lydia it's not like he ever imagined he had some sort of a chance, but he's known her as long as anyone. She's always been brilliant and ruthless, and yeah, there've been moments over the years when he's hated her more than anyone else on the planet, but by and large she's been the one thing that made working for the Martin family bearable. For the last two years he's been part of a shrinking skeleton crew of staff left in the tower, and with Lydia's friendship with Allison already blurring the lines between the ranks it's been harder than ever to keep up the old boundaries. Even if they're not exactly friendly, everyone left here has gotten to know everyone else a lot better than they were ever supposed to since Lord Martin rode away.

So even knowing it was written on the wall that nothing could ever happen, Stiles has entertained the odd fantasy or seven about himself and Lydia over the years. It's not like that would've been news to anyone around here, least of all Jackson, and nevermind that a would-be-knight like Jackson was hardly that much closer to being Martin-family wedding material. Heck, Jackson barely passes muster as a knight; if Stiles is hardly subtle with his thing for Lydia, then Jackson's positively transparent with his fears that some day the wrong person is going to notice that his status as a foundling leaves him without proof there's nearly enough noble blood in his ancestry to qualify him to be a knight at all. If anything, the one thing that made dealing with Jackson's scorn remotely bearable was knowing that when push came to shove, he shouldn't have had any more chance with her than Stiles did. 

He knows better than to make it personal, but if Lydia had to choose someone below her station... why did it have to be _him_? 

Stiles doesn't know how long he stands there, watching what he shouldn't because he can't look away. But whether it's one minute or ten or a hundred, somehow it's not the surprise it should be to become aware of the warm bulk of another body there in the dark behind him, or to hear Derek's voice murmuring into his ear, "This isn't the first time they've done this, you know." 

There's a tightness in the back of Stiles' throat as Derek's arms settle around his shoulders from behind, the better to whisper in his ear like the devil on his shoulder, presumably. Stiles tells himself he is not, _not_ going to cry just because Lydia chose Jackson over him, and like hell he's going to do it in front of Derek, who can promise whatever he likes but still clearly couldn't pass up a chance to watch him embarrass himself in front of Lydia.

"Maybe you can imagine what it was like for her," Derek whispers, "waking out of a demon's thrall, somewhere completely dark, in a bed that isn't your own. Some of the effects dissipate immediately – if they hadn't you'd never have woken at all; but the _need_ burning through you – that's something physical. That doesn't go away so easily."

The edge of a wing flickers through Stiles' peripheral vision, and he feels something – that second set of fingers on the elbow joint, whatever you call them – stroke gently over his hair.

"You have some idea what happened to you, but it's not that clear, and the only people around to help are two boys who understand even less of this than you yourself do. One of them is so glad to see you revived that, even though he usually wouldn't dare, he grabs you and hugs you tight to his chest. Suddenly all that _want_ has something to focus on. 

"Or _maybe_ ," Derek goes on, "that's just what you tell him – what you tell yourself – the price of the right to ask for something you've wanted from him for years; maybe as long as he has. But none of that really matters when all you know and all you care about is that there's nothing in the world you want more now than for someone to hold you and help you show yourself you're _alive_. Your boy probably protests at first; he's almost as scared as you are; doesn't know if he can trust it's really him you're seeing, but that's just all the more reason to show him how _very_ sure you are."

The hell of it is, Stiles _does_ know. Laid out like that it's easy to picture and so easy to believe that's exactly what Lydia must have gone through. The fear and the confusion – all the worst parts of his last two incredible encounters with Derek rolled into one – all overlain by _need_ too powerful to deny. But regardless of whether it would be fair to hold it against her for giving in, he's not sure he needs to know as much as Derek's telling him. Just how long _had_ it been between when Scott had left Lydia in Jackson's room that morning and when Lydia herself had appeared outside to see the dead incubus for herself? Is that when they'd done it? Or had they waited until after, when Lydia commanded them to burn the body and Jackson followed her back inside, and hadn't come back out to help for – for Stiles couldn't remember how long. 

"Later," whispers Derek, "a couple of days after, when it's all over and just as you're starting to feel like everything's back to normal, someone tells you the danger might not be over after all. Stands to reason you're not going to take that so well. The last thing you're going to want to do is spend the night alone."

"Alright, I get it, okay?" Stiles mumbles, but Derek doesn't seem to be done. 

"Do you?" he says. "You've got to marvel at how it all falls out. Nothing goes to plan, and yet, looking back, someone could almost believe it was meant to happen this way. It's amazing just how much you humans carry around in secret, lurking right underneath your skin as long as we're not around to draw it out for you. Just think – in a few years, she might even look back on this and be grateful."

This last comment finally penetrates far enough into the fugue state of Stiles' mind to catapult him out of his silence. "Oh yeah, just think, if one of _you_ hadn't shown up and tried to kill her, she might have had to come up with her own excuse to screw that prick mooning over her. I bet that balances things right up for her. I bet she'd be real happy knowing that."

He'd almost forgotten what it sounded like to hear Derek chuckle. "See, that's what I like about you, Stiles. You never stop pushing back."

Stiles takes a shaky breath, and reminds himself he is notgoing let this latest off-hand comment suggesting Derek actually likes him make him weak at the knees. "That what you say to all the boys?"

"No," Derek says, simply, giving Stiles nothing to work with. "Just what is it that makes you tick, Stiles? You never stop fighting me – not because you don't want me, but because you don't want to _waste_ any part of me. You have to understand everything; dig your fingers around it and turn it over and over until you know it by heart."

"Deaton says it shows an inquiring mind."

"Careful," Derek murmurs, smiling against his skin, "It's going to get you into trouble some day."

"Really?" Now Stiles is the one almost laughing. "When do you think that might be?"

"How about the day you fell for her?" says Derek, which: _ow_ , low blow. "It never was enough for her to be the unattainable princess, was it? You had to keep worrying at what attracted you to her until you found out how brilliant she was; until it almost killed you to think she might have to settle for someone who never even noticed. And then she goes for _him_."

Wonderful – inarguable confirmation that Derek has been reading his mind, and it still doesn't hardly matter to Stiles compared to the ongoing thorn in his side of knowing _Jackson_ would be the one Lydia sought out in a moment of weakness. Through the doorway at the end of the hall, caught in one of her most intimate moments, Lydia looks further away from Stiles than she ever has been before. 

"That what you came back here for? To gloat to my face? Or the back of my neck, if that's what works for you." Like Derek hasn't been keeping tally of everything Stiles has got wrong since the hour they met.

"Maybe I came here to comfort you," Derek whispers against the shell of his ear. Somewhere during the preceding exchange, Stiles has missed the point where Derek's hands found their way under his clothes to rest on his stomach like a promise. 

Stiles himself is not in the mood to be so easily swayed. "You call this comforting?"

"No," says Derek, "Unfortunately, the truth tends not to be. But I can be _very_ distracting, if you'd like." 

"Starting to think you think I'm easy," Stiles grumbles. "Oh hey, speaking of distractions," he adds, craning his head around and doing his best to look Derek in the eye, "you went for _Kate?_ Kate _Argent?_ What in hell is wrong with you?"

Derek gives a short, impatient sigh, and Stiles would be congratulating himself for hitting a nerve if the whole idea hadn't been playing a merry tune with his own nerves all day. "Putting aside why you'd even assume that was _me_..."

"Oh my god, _seriously_?"

"Do I have to remind you what I am? It's what we _do_." What Derek is doing now involves pushing his hands down Stiles' pants to hold him by the hipbones. Stiles doesn't feel this helps his point. 

"What you _do_ is pick on _hunters?_ One of, like, _five people_ on this side of the country who might actually know how to kill you, and you pick _her_?" 

"She was alone, in the wilds, at night – an easy target," says Derek, pronouncing each word with a ringing finality. "I didn't know she was a hunter."

Stiles feels his eyebrows winch up in disbelief. "Which part of that scenario _doesn't_ scream hunter?"

"Stiles, I _killed_ one of my own the other night. It didn't leave me in the best of states. As someone pointed out, I needed _more_ than what just you could give me."

"You know," says Stiles, "I'd take that as an insult if you hadn't come _crawling_ back to me after she shivved you and you ran off." Stiles gave up on trying to remember if there'd been so much as a mark left in evidence on Derek's body that day; he can't force himself to remember, and it stands to reason a demon could heal at least as fast as Scott does. "And for another thing, are you not even picking the irony of how you're calling _me_ stupid when _you're_ the one who went up to the hunters, practically announced your existence and threw away that perfect cover story you made me help you put together?"

Unluckily for Stiles, this perfect take-that rant only seems to shove Derek right back onto his game again. "Worried about me, Stiles?" Derek's breath tickles the back of his neck; playful, almost. "Or is this sudden fixation on that hunter pure jealousy?"

"Oh, you're one to talk about jealousy when I get one glimpse of Lydia in her intimates and you come running back," Stiles grouches. 

Derek chuckles again, another faint shiver against his skin. "You like the idea of me being jealous, Stiles? I have to admit, it doesn't reflect terribly well on me if we can go two rounds and the sight of your old crush moving on still brings you to your knees."

Stiles catches his breath again with difficulty. He'd been doing so well so far, but he hadn't been close to prepared for Derek to allow him even that much. One of them was going to have to capitulate here eventually, but he hadn't counted on it being that easy. "Is this where we go a third round just to settle things?" he asks. 

"You tell me, Stiles." Over Derek's hands, Stiles pants' have already slipped down enough that there's a sliver of Derek's body pushed skin to skin against him, hard and ready for this. "Would you find that comforting?" 

'Comforting' may not have been the first word Stiles would have chosen, but with Derek right here it would be so easy – would be impossible _not_ to find himself all but overwhelmed by the memory of what it was like to feel Derek inside him, and with inspiration like that Stiles doesn't care how petty it is to console himself with knowing there's no way anything Jackson's getting in there could be close to as good as what Stiles has had with Derek. What Derek's offering him again.

" _Yes_ ," Stiles breathes, " _God_ , yes."

That's all it takes; there's all of the time for Stiles to feel a flash of air against his bare legs before Derek's sliding into him, right there in the corridor, only a hall away from Lydia's room. Stiles chokes off the noise he makes, desperate to keep quiet, silently relieved when Derek tugs him just around the corner so he can lean on the wall, tucked away out of sight. From there on, there's not much talk at all. 

It's slow, this time; the pace Derek sets utterly languid, his hands roaming Stiles' chest and stroking up the inside of his thighs. Stiles finds he doesn't mind; the urgency of the last two times isn't there, and that gives him the opportunity to commit to memory every last detail, just in case this really is the last time like Derek keeps threatening it will be. 

After, when Stiles' knees really do give way, Derek holds him and eases him down to the floor, and stays until Stiles' breathing evens out again. 

He wakes up in his own bed the next morning without any recollection of how Derek got him down there, but there's not even a whisper of an inclination to believe that anything that happened last night was a dream.


	4. Chapter 4

So it figures that just when Stiles was getting used to having his life threatened and all his assumptions overturned on a daily basis, his next morning is so close to uneventful it's almost a let down. No new revelations, no new monsters, nothing. Life could almost be declared 'back to normal'.

Scott and Alison are still sneaking around doing their tragic love story that Stiles is all but convinced _everyone_ in the tower except Chris already knows about. Scott's still sneaking around being the secret werewolf that everyone but Lydia and the hunters already knows about. Lydia and Jackson are apparently now running their own secret, tragic – or just profoundly nausea-inducing – love story behind the scenes somewhere. And Stiles finally has some secrets of his own. Well, whatever.

Knowing what he knows about Lydia and Jackson still hurts today, but it hurts like an old ache, something he's had months to get used to rather than hours. Okay, so she's sleeping with Jackson – compared to some of her other suitors, even he's not _that_ bad. It's not like it means she's going to marry him. It's not like it means she's doing any more than messing around with him for a little fun and a little post-near-death-experience comfort. _Instead_ of Stiles, which is probably for the best because it's not like Stiles could ever have dealt with being someone Lydia only went to for a little fun.

Yeah, so he's still more than a little bitter, but the whole time he was in the same room as Lydia this morning it hardly even stung. When he thinks about the possibility of switching places with Jackson, getting Lydia but never having Derek at all, it doesn't sting at all.

Stiles figures he can put off analysing that one too closely for at least another day or two. He's earned that much for all his trouble.

The one thing that does happen to Stiles that day involves getting cornered unexpectedly by Chris Argent. There's no escape; Chris can corner a person without a corner or even a _wall_ within a dozen paces, and that's exactly what he does when Stiles runs into him out by the wood pile.

"Oh, hey," says Stiles, realising too late he's not the only one to choose this moment to go out for more firewood. "After you. I'll come back later."

He gets as far as turning around before Chris calls his name. "Why waste your trip? There's plenty to go around. Besides, I've been meaning to talk to you."

"What about?" asks Stiles, like he really doesn't know, eyeing the log pile and judging his distance. Maybe if he makes a dash for it he can grab a couple of logs, make an excuse about the cold and be back inside before this can get personal.

Chris smiles. He has a couple of different ways of smiling, none of which Stiles likes very much, and today doesn't look like being the day he finally invents one. He says, "I understand we have you to thank for ridding us of one of our incubi the other night."

"Well, you know," says Stiles, edging his way closer only to find Chris still seems to be in his way from every possible angle, "someone had to do something, and it's only what Deaton's been teaching me to do... you know, ever since _that time_ all those _years_ ago when he caught me stealing his supplies and decided I needed to learn exactly how many horrible things could have gone horribly wrong for me." In other circumstances, Stiles would voluntarily raise that little historical gem only under extreme duress, but all past experience with Chris assures him it's only going to get brought up _for_ him if he doesn't get there first. Unfortunately, it seems today _is_ the day when one of the Argents finally recognises that Deaton's efforts with Stiles amount to more than a creative form of discipline.

"Don't be so modest. I had no idea you'd come so far," says Chris. "You've been holding out on us."

"I wouldn't look at it as holding out so much as... not rushing into things before I'm ready," Stiles clarifies. "Deaton has very firm opinions and a few very colourful sayings on the topic of apprentices who go out looking for trouble before they're qualified to handle it. Common sense."

Chris gives him a different smile. This one suggests slightly too much amusement at Stiles' definition of 'common sense'. "In my experience, you never know what you're ready for until you're tested. It's at times like this, when we come under adversity, we find out what our friends are really made of." Chris puts a 'friendly' hand on Stiles' shoulder. "I can see you're going to be a great asset to us someday."

Stiles fidgets and tries to find a take on that statement which implies he gets a say in the matter. "Who knows? I guess I could surprise you yet."

Chris' smile broadens. "There's still another incubus out there. Your chance might come sooner than you think."

The need to _ask_ wars briefly with the urge to cut this conversation as short as possible. "Um. About that." Oh, what the hell. Like Stiles has ever gone with 'shut up' when there's any other option. "Do incubi normally travel around in pairs?"

Chris raises his eyebrows and folds his arms. "You tell me, Stiles. Aren't you the expert now?"

"Well," says Stiles, "for one, I got one lucky shot in, that doesn't make me an expert. And for another, nothing I've ever read about incubi said they travel in groups, and _everything_ says there hasn't been a single incubus around these parts in over a hundred years. So there's a gap in my knowledge somewhere and I'd rather fill it by asking the right questions than by waiting until we find out there's twenty more of them out there all after me for revenge." He's learning to love lying by implication on subjects that would've made him nervous even if everything he was saying had been the truth. " _Or_ whether I can sleep easy knowing the other one is busy putting half a continent between itself and your sister. Which is what it'll be doing right now if it has any sense."

Chris smiles. Again. "You know _why_ there hasn't been an incubus seen in this country in a hundred years?"

Stiles should have known better than to hope for anything so simple as a straight answer for his trouble. "Okay. Enlighten me."

"What you need to understand about incubi," Chris turns to the wood pile, because naturally you only add to the effect of a lecture by casually doing something else all the time you're talking, "is that they have more in common with the common werewolf than most people realise. One bite, or one touch, that's all they need to enslave their victims to the basest of their instincts. For the wolves, it's aggression, whereas for the incubus, that base drive is _lust_. Even for the best of us, desires that primal can be hard to resist."

Stiles feels a person could happily go their whole life without having to hear Chris Argent pronounce the word _lust_.

"With your reason overcome, what's left of you is easy prey for the will of the alpha – or for the demon." Chris hefts a good solid piece of wood up for inspection. "We're lucky our incubus only sent Lydia to sleep; if she'd been conscious she would have done whatever the demon wanted her to do."

Stiles shifts his weight impatiently. ( _Not_ nervously. Definitely no nerves happening.) "Is this building to a point of some kind?"

"Oh, but you see," Chris waves his log toward Stiles for emphasis, "the _real_ difference is what happens next. A werewolf bite can add you to his pack, but all a demon can do is kill you. They can't turn humans, and they don't have that same power over their own kind. That's why when you meet one, it's always going to be alone. And you see, Stiles, once you know their weaknesses, picking them off isn't so hard as you might think. My family's known about those weaknesses for a number of generations."

"Okay," says Stiles, "this is fascinating, but maybe I could repeat my question for you..."

"You want me to speculate as to how we got two incubi in a place where none have been seen for generations?" Outwardly, Chris sounds confident enough, but something in his inflection over the word 'speculate' delivers Stiles a rare flash of insight.

"You don't have any more idea than I do, do you?" Presumably even _less_ idea than Stiles, if Chris can dissemble this long without producing any good alternative to Derek's version of events.

"Not yet," says Chris lightly, apparently unthreatened by his own ignorance. "One incubus might be no more than a lone rogue looking for new territory, but _two_ – that suggests something more sinister than mere coincidence. But if we catch ourselves that second demon, we might just find out what."

Stiles is in the middle of sorting this new non-surprise into his worldview and awarding one more grudging point for to the Derek side of the Incubus/Hunter Credibility Showdown when Chris drops his real bombshell, "Come by our quarters at sunset today; you might just be able to help out."

The concentrated efforts of Stiles' father over the years of his short, uninteresting childhood mean that Stiles has only ever learned a few really good swearwords. None of them seem quite sufficient right at this moment.

Chris goes right on like nothing has happened. "One way or another, we'll be seeing it again, Stiles. But I'd sleep easy for now, if I were you." He gives Stiles one last smile for good measure, finishes grabbing himself some wood and heads back inside.

"Thanks," Stiles calls after him. "That's very reassuring."

Good sarcasm is wasted on the Argents.

* * *

So. Chris wants Stiles to 'help out' with whatever brilliant idea the hunters have concocted for tracking down Derek. That doesn't necessarily mean they know he's hiding something, but any excuse he makes to get out of showing up is going to look pretty damning if they do, and pretty suspicious even if they don't. Stiles has been a member of the serving classes long enough to recognise that just because Mr Argent had couched his invitation in terms of 'should's and 'might's doesn't mean he was giving Stiles the liberty to treat it as a suggestion. So as the sun dips below the tree line, instead of arranging to be horribly busy with his regular chores or giving Lydia excuses to find him more work to do, Stiles makes his way downstairs.

The hunters' quarters take up most of the ground floor not already spoken for by the kitchens and store rooms. He's been down here a handful of times before on one errand or another, but by and large the hunters don't have a lot of use for servants. They tend their own horses, they sweep their own floors, and you'd better believe they sharpen their own swords. Hunters have their pride, and they trust no-one outside their own circle around their gear.

Kate meets him at the door with that classic Argent smile. "If it isn't the man of the hour. Ready to see if you can make two demons for two?"

"Yeah, about that," says Stiles, crossing the threshold with all the enthusiasm of the condemned, "maybe if we look at what happened the other night as more of a fluke and..." and that's as far as he gets before he gets a good look at what's waiting for him inside. " _Oh_."

Space in the main meeting room isn't so much cluttered as _unwasted_. Bookshelves or cabinets filled with maps and journals cover most of the wall, what space is left between them bristling with rows of hooks holding up coils of rope and netting or a hundred variations on the theme of sharpened metal. If the hunters want to debate the merits of the perfect tool for a very particular job in here, they don't intend to go far for a demonstration model – the intimidation factor, he's sure, is purely incidental. But this is background stuff, nothing he hasn't seen on previous visits; Stiles' attention goes straight to what the hunters have set up on the long oak table taking up the centre of the room. Whereas that table has always been covered in maps and reference material when he's been here before, this time it's bare but for a set of runestones placed to mark the four cardinal directions and a small unornamented dagger, hanging by its balance point on a length of twine strung from the peak of a three-legged metal stand. The blade, a little less than one hand-width in length, is dark with dried blood.

Elsewhere in the room, Chris Argent is saying something like, "Stiles, pleased you could join us," but Stiles would be paying more attention if he hadn't been preoccupied just at that moment remembering being told _Kate wounded the incubus before it got away._

Stiles hears himself say, "Is that... _its_ blood?" Any peasant knows there are two kinds of magic in the world, broadly speaking: the kind people like Deaton use to nullify a poison or keep monsters out of your home, which is perfectly respectable; and the kind your unsavoury neighbour uses to summon soul-stealing demons or make your cow go dry, which will have you burnt at the stake as a witch at the minutest implication of guilt. The line between the two gets a little blurry in places, but Stiles is pretty sure anything that involves a dagger coated in _demon's blood_ has to be the kind of magic you wouldn't want to admit even _knowing_ about, let alone in the presence of hunters.

Out of the corner of his eye, he sees the two Argents exchange glances. "Not much gets past him, does it?" says Kate.

Stiles looks up to catch the look on Chris' face as he says, "I see we won't need to trouble ourselves overmuch with explanations."

"Uh, actually why don't you take me through what you're doing here," Stiles says, slowly. "Make sure we're all on the same page."

Kate flicks a look toward her brother and sits herself on the edge of the table between Stiles and their set up, though also slightly past the edge of what Stiles considers his normal personal space. "Well, obviously I'm no _expert_ ," she says, "but as _I_ understand, the principle at work here is _like_ calls to _like_." Producing another dagger from somewhere, she uses it to indicate the set up on the table, then holds it up to contemplate the gleam of the metal. "A blade that tasted demon flesh once will long to again. All it should take is a little push to get it started, and _bang –_ it'll point us the way."

Stiles is reasonably proud of how he only flinches a little bit when Kate's dagger inevitable finishes this display pointed sharply at his nose.

"It's no easy task, tracking a creature with wings," Chris puts in. "At least if you're going in cold. If we're going to find it, first we're going to need something to point us in the right direction."

"Okay. Sounds like you've got it sorted," says Stiles, carefully, going only a little cross-eyed. "What was it you need me for again?"

Kate mercifully leans away, taking her dagger with her. "Well, there's the problem. We just can't seem to make it work. Any thoughts on why might that be, Stiles?"

"Because a demon just died here." The answer is out before Stiles has even thought about it, recited on rote. "You can't track demon blood without finding residue everywhere. An effect like that isn't going to clear overnight."

"And roughly how long do you think that might take?" Kate prompts.

"Um. A change in the season might do it."

Kate gives an elaborate shrug. "I'm afraid that's going to be longer than we can afford to wait."

"My sister has some experience with invocations," says Chris, "but it's not our area of expertise. It could be this one's beyond us. But before we give up on our best lead, it would be a waste not to see if our own magician in training couldn't get better results."

Yeah, the time for stalling is officially over. Stiles takes a long look between them, and does his best not to swallow around a very dry throat. "This isn't something I've done before. And demonic interference is _not_ something you can just shrug off, practice or no practice; I wouldn't want to get your hopes up I'm-"

"Come on, Stiles," Kate croons, pulling back a chair by their experimental set up invitingly. "You learn by doing."

Stiles gives them the stiffest of nods and moves towards the chair like a man already in a trance. He watches the dagger vibrate on its string as he sits down. You could just about hear a pin drop in here right now.

"Okay," he says. "If I'm going to do this, can I do it with a little more elbow room?"

Kate raises her eyebrows at him, but she moves herself to the far corner of the table opposite Chris, putting her within Stiles' field of vision but no longer right under his nose.

Theoretically, Kate should be a better person than Stiles to be doing something like this; she was the one holding that dagger when it got that bloody stain. If Stiles can make it work where she couldn't, will that show the hunters he has a 'connection' with the demon that they don't? Or if he fails (or pretends to), will they take _that_ as evidence he's in league with the demon? What if he _can't_ make it work? What it just being involved in this makes Derek even angrier than he was about the geas? What if doing this _triggers_ his geas again? What if when the dagger stops spinning, it points to _him_? 

Does he actually _want_ to lead the hunters to Derek? He'd be lying if he pretended he had any idea what he's supposed to make of Derek – he definitely doesn't trust the guy, demon or not – but that doesn't mean Stiles wants him _dead_.

Can he even make this work at all?

No matter which way you turn the rest of this, the one thing here Stiles can't lie or confuse himself about is that... he does kinda want to _know_. And the hunters have been nice enough to take all actual choice out of his hands here.

He takes a deep breath and pushes all that uncertainty out of his mind. When he feels like he's ready, he catches one finger against the twine and gives it a sharp tug to send the dagger spinning in crazy circles, swinging on its axis with enough energy that the whole frame judders along the table by half an inch. As the spinning slows, something in the motion starts to go wrong, like the weight has changed or the balance is off – not by much, just enough to leave you playing with dice that will roll you a six four times out of ten. By the time the dagger finally stills it's settled on a direction quite different from the one it started out in.

There's one last horrible moment when Stiles leans in for a better look where his stupid, quivering knee develops a mind of its own and whacks into the table leg, making everything on the table shake and the metal stand ring with the vibration. But the dagger simply twists a little to the left, then the little to the right, then settles right back to its chosen orientation with the certainty of a compass needle answering a subtle magnetic pull.

Stiles stares at it mutely, struck by the discovery that _believing_ you can do something – even believing hard enough to make it work – is still a very different thing from _seeing_ it work for real. He raises his eyes to the Argents, both rapt as he is.

No power on earth could have kept the little trace of smugness out of Stiles voice when he says, "That looks to me like a result."

"Almost due east." Chris has a compass on the table and is unrolling a map before Stiles knows where he got it from. "That would put us..." Already he's tracing roads and trails along the contours of the map, Stiles practically forgotten. "We need to be in the saddle before it moves again."

"Nice work, kiddo," says Kate, dropping a hand on his shoulder which passes for congratulatory for all of a second or two before she's nudging him towards the door. "Your father would be proud."

What should have been a compliment hits him like a slap across the face. Stiles doesn't remember a whole lot of what happens between there and when he finds himself staring at the bottom step of the tower staircase after being turned out of there, trying to figure out where the hell he's supposed to go from here.

* * *

Allison's not part of the hunt tonight and she and Scott are taking advantage of the opportunity for an evening rendezvous, which isn't unusual and wouldn't even be notable except that Stiles has never really gotten used to sleeping alone. The one good thing about growing up having to share your sleeping space with too many other people is that even the most imaginative young mind has to work very hard to convince itself there are monsters under the bed. The bad part is that these days, Stiles is old enough to know damn well the monsters are real, and when you leave him to put himself to bed in _perfect silence_ , sleep can quickly cease to be a thing that happens at all. He lies there in bed, _not_ thinking about what Scott and Allison are probably doing right at this moment, and _not_ thinking about what Lydia and Jackson might be doing now too, and definitely _not_ thinking about what any of the hunters are doing – whether they've found and murdered Derek by now, or whether Derek's found and slaughtered _them_ , and whether it's all Stiles' fault for orchestrating it whichever way its going. An hour later all he has to show for it is new evidence that _not_ thinking is something he'll never be good at.

He obviously has zero hope of keeping himself from turning everything over and over in his head tonight, so he might as well get started on it. Three shockingly intimate encounters in the space of days haven't hardly done him any good sorting out just what he's supposed to _do_ with Derek. Derek may have saved his life, but Stiles isn't stupid enough to imagine that was much more than happy accident. He doesn't owe Derek _jack_. Even _Derek_ would probably agree Stiles owes him nothing but geas-bound silence. But given any actual say in the matter, he'd rather not have Derek's death on his conscience. Even if Stiles might have been willing to grant the hunters _some_ sort of authority on the subject of demons, Derek's still not the one who's been keeping his best friend living in fear for his life for the last however-many-moons, and Chris already blew his chance on that one today. If the hunters _do_ find Derek tonight because Stiles pointed them right at him... well, safe to say Stiles isn't going to sleep any better for knowing that. Probably not for a long time.

It'd be nice if Derek himself had offered a little more help in untangling what Stiles is supposed to do with all this. Between all his half-answers and cryptic bullshit Stiles feels almost like he knows _less_ about incubi than he did this time last week. He's not really _scared_ of Derek at this point; the scary part isn't the guy himself so much as the abstract of what he represents, which would be something closer to a bottomless cavern of the unknown, surrounded by the thorny brambles of well-founded suspicion. All his books will tell him is that incubi are dangerous and not to be trusted. The one thing both Derek _and_ Chris almost seem to agree on, going by their various veiled hints, is that Stiles is way out of his depth and should have the sense to stay well away from what he doesn't understand – except in the parts where he's expected to play his role like a good little accomplice, of course. Chris has never had much use for subtlety; his spiel about how good incubi are at messing with your mind was meant to make Stiles question who he could trust, while conveniently establishing the hunters as the one infallible authority on the subject. If he were born a little more gullible, Stiles would be wondering whether he could trust himself right now. Hell, maybe he _is_ a little; but he still trusts Chris a whole lot less.

He _definitely_ doesn't trust Derek. But however you look at it, he's never _felt_ free-will impaired when the neighbourhood incubus is around. Okay, there was that one time Derek held him down until he'd promised to keep the encounter secret, but he can't see why Derek would have bothered if one touch could have wiped away his choice altogether. The only substantial threat he's thrown at Stiles since is the one about leaving him with blue balls if he wouldn't cooperate, and Stiles can't say he took that very seriously even in the heat of the moment. If anything, Derek acted like he was _insulted_ by the idea he'd need magical manipulation to get what he wanted out of Stiles, and yeah, Stiles can't really argue that point. The uncontrollable lust brought on by Derek's mere presence is definitely a thing, but as far as Stiles is concerned, you'd have to be pretty much dead not to find Derek appealing. Above all, there's no way he can imagine Derek would have put up with all those annoying questions if he could have shut him up with a thought. Meanwhile, the only sure lie Derek's ever told him is the one where he keeps promising he's not coming back, and for all Stiles knows, he's been lying to both of them on that account.

No matter how he looks at it, he eventually comes back to this: Derek is 1) an idiot, 2) an asshole, and 3) a literal, bona-fide demon, who enjoys messing with Stiles' head and probably abstains from serial murder only for reasons pertaining to his own self-interest. None of which makes for terribly compelling evidence that Derek deserves to die.

Of course, it'd be easier to hang onto that if Derek didn't also have mind control powers, not to mention fangs, claws, and a disturbing propensity for spying on Stiles' private life and dropping in whenever he pleases. For all he really knows, Derek's perfectly aware of everything Stiles has been through today. For all he knows, his 'magic' on the dagger was nothing more than a carefully arranged demonic illusion; the hunters are off on a wild goose, and Derek has been pulling his strings to set this up all along for his own amusement. And the sickening part? Stiles thinks he might just be _okay_ with that, if Derek had only had the decency to let him in on it, rather than leave him lying here wondering whether Derek has any idea what's coming for him.

The only times he's been _sure_ Derek must have read his mind are the time he triggered the geas (which might not even count) and the time Derek caught him skulking in the corridor after nearly walking in on Lydia and Jackson. For all he knows, incubi are just specifically wired to pick up on extreme sexual frustration from past or future victims, and everything else was theatre and demonic-hearing-espionage. Well, the joke's on _Derek_ if that's what he's stuck hearing from Stiles – especially on a night like tonight, when he's way past having the patience for any qualms about resorting to the traditional sleep aids of teenage boys.

Stiles rolls onto his back, shuts his eyes and lets his mind wander. He tries out the idea Derek had tried to plant in his head the other night – the one about what it might have been like if there'd been no other incubus, so when Stiles had burst into Lydia's room ( _alone_ , this time – Scott and Jackson mysteriously unavailable) thinking her under attack, it had been _Derek_ and Lydia on the bed; her hands in his hair, his own cupping the curve of her breast through the lacing of her gown; Stiles' sudden entrance interrupting them the midst of languidly exploring each other, mouth to mouth. They stare at him for all of an awkward few seconds before Derek gives him an evil smile and says, "Like to join us?" while doing something to Lydia's chest that makes her arch into his touch. Lydia flicks a look at him from the pillow and raises an eyebrow, "In or out, Stiles. Come on."

Stiles is over there and on the bed before he can think twice; then Lydia is undoing his belt while Derek sucks kiss after kiss into his neck, hands already under his clothes, encircling his waist from behind. Lydia pushes his tunic off his shoulders, then Derek is turning him around and pushing him down into the bed so his head is almost in her lap, but somewhere after that he loses track of Lydia a bit and she winds up not so involved – it's so much _easier_ to picture things with Derek with so much inspiration to draw from. So Lydia lounges against her pillow and watches as Derek presses him back into the bed and makes a show of taking him apart, hungry and possessive, eager to show off his conquest to a willing audience...

When Stiles opens his eyes again, Derek is the first thing they land on.

"Hiiiiii!" Stiles grins at him. "I was just thinking about you!"

Derek looks less than happy about being here, but Stiles is about decided that's the only expression he's got beside 'seductive', and when your partner comes pre-seduced before you even arrive that's got to throw you off your game a little. "This is a dangerous game you're playing, Stiles."

" _I'm_ playing? Pretty sure _I'm_ not the one the hunters are going to tear limb from limb if they catch us." Stiles pushes his sheets back a bit and pats the bed beside him invitingly. "Which they won't, by the way, since they're riding off somewhere east of here tonight. You should stay in with me where it's safe." He goes on beaming – and Derek goes on glowering – while he takes the invitation to climb into Stiles' space.

"You really think it doesn't mean anything for you to do this – _summon_ me here, knowingly?" says Derek, well into his looming routine, though he hasn't put a hand on Stiles yet.

"Means I get you," Stiles points out. Derek huffs at him and looks away. "Hey, _someone_ gave me this spiel about how every roll in the hay I ever had left to look forward to without him was gonna be a let down. So either you're _it_ , or you don't deal so well with the idea you're _not_. What can I say, if two nights with me is enough to make a guy jealous of people I haven't even _been with_ yet, it's not like I can't take a hint, you know?"

Stiles watches the muscles of Derek's jaw working soundlessly. He's still not making eye contact, and Stiles wonders if this is what, by Derek's standards, passes for 'contrite'. "Stiles..."

"Look, Derek, I _get_ it, okay?" Stiles reaches for him, tries to get Derek to turn his face far enough that he can see how serious he's being. "I'm pretty sure I've got this figured out. You don't kill people, so there's no body, nothing – you don't even leave _bruises_ for crying out loud. No-one knows anything more happened than someone had a re- _eally_ good dream. The hunters don't come after you because they don't know there's anyone _to_ come after. But _I_ already know about you, and you already made sure _I_ can't tell anyone, and I'm here and I'm easy, and that's gotta be a whole lot _less_ trouble than crawling in someone else's window tonight. Plus, I come with a front row seat to the local hunter show, and I know exactly when they're going to be out for the night. You can trust me, Derek, I'm _really_ invested in keeping this on the down low."

The corner of Derek's mouth quirks a little. "Right. No personal feelings, no compromised judgement involved."

Stiles shrugs it off. "Okay, you got me, the thought of someone else getting to go next with you makes me a little jealous too. I can admit that. By the way, I'm thinking we're going to do it face-to-face today. I really liked watching you come that first time."

Derek shakes his head and for a moment, Stiles thinks he looks almost _fond_. "I knew you were going to be trouble."

"And you came back to see me anyway – _three times!_ What kind of message is that supposed to send a guy?"

"You _would_ take that as a compliment," Derek mutters, and kisses Stiles before he can lose the last word.


	5. Chapter 5

**Notes for the Chapter:**

> The Derek POV side-story [What Lies Beneath](http://archiveofourown.org/works/2096991) fits into the timeline around the early part of this chapter, though can really be read more or less any time between here and around chapter 10 or so (or whenever you feel like it's been a little long since the main story delivered the last _proper_ bit of Derek/Stiles smut along the way).

So that's how Stiles winds up sleeping with an incubus. 

He'd tell you it all made sense at the time, but he's not sure who he'd expect to buy it. 

It's not as though he hasn't considered the long list of ways in which this is probably a terrible idea. Derek may have denied any active interest in dining on the flesh of nubile virgins, but he's still an unknown quantity at best. Stiles could count on one hand the number of times he's had a straight answer out of Derek on anything down to the most innocuous of questions. ("Should I be eating more, now you're doing this with me all the time? Am I, like, eating for two now?" he'd asked once, when Derek had arrived to find Stiles enjoying one of last year's apples, fished from the bottom of the last barrels in their food stores. "Hey, do you need to eat regular food, or are you sustaining yourself solely on the pleasure of my company?" Derek had glared at him, then stolen Stiles' apple and taken a large, slow bite out of it, holding Stiles' gaze as he swallowed, then licked the juice from his lips; and when he'd tossed the remnant away and climbed into Stiles' space, Stiles had completely forgotten what they'd been talking about.) 

Considering Derek's surly attitude to the whole affair, an outside observer could be forgiven for assuming it was Stiles who coerced _him_ into this – and seriously, _whatever_ ; Stiles would never have imagined this thing they're doing was even an _option_ until the third time Derek had taken it into his head to crawl in through a window and have his way with the same lowly servant boy. If anything, Derek's intermittent allusions to how Stiles should know better have only been feeding his urge to be contrary. Or maybe, once in a while, even given him the excuse to entertain the fantasy that they're both in this together, and Derek has no more idea what they're doing than he does. 

For the record, Stiles does understand the concept of reverse psychology, and yes, he _has_ entertained the thought that Derek's non-specific warnings are part of a long and elaborate set-up that will end with him laughing in Stiles' face when he learns he's inadvertently sold his soul to the devil. But then he remembers that time when Derek went after _Kate_ , and the idea that Derek's capable of anything so diabolically clever sounds like the set up for a joke. 

When all else fails, the thought of how hard either of the elder Argents would disapprove of what he's doing with Derek is just about all the justification Stiles needs. 

Speaking of whom, that minor issue of how Stiles has yet to successfully lead the hunters to the incubus hasn't discouraged them from trying. Every couple of days, they have him retry his trick with the dagger and ride out to wherever Stiles points them – usually making it home some hours later without so much as a glimpse of a wing-tip to show for the effort. And maybe Stiles isn't entirely innocent on that account, but all considered he's not hugely worried that what little he's done to nudge the odds one way or another is going to get him caught. 

("Look, just because I can point you to where he _was_ doesn't mean he's gonna stay there," he'd told them the other night. "Incubi have _wings_ and all, and there's a whole forest out there for him to hide in."

"Oh, our local demon's a 'he' now, is it? Cute," said Kate, raising an eyebrow, but hell if Stiles was going to get caught out on a slip-up that basic.

"I'm pretty sure we're not dealing with a 'she', are we? Yes, _he_ – it's a lot easier to make this work if I think of _him_ as more than just some dumb animal. Like one who's smart enough to _move_ right after our best window for this."

"A convenient excuse," said Chris. "And a very neat way to avoid being questioned on how you can be so sure you're doing this _right_. It's good to know all those years of hauling water having given you such a keen insight into demonic psychology."

That one got a real eye-roll from Stiles. "If I _didn't_ believe I could do this, you wouldn't be seeing any result at all. That's how magic _works_. Any time you lot wanna go back to hunting the old fashioned way, no skin off my nose. I've got plenty of _water-hauling_ to keep me busy."

The Argents _really hate_ being made to feel like anyone else is in charge.)

He's not forgotten about the real chance the hunters really will get the drop on Derek one of these days, though – or the equally real chance he's going to be their unwilling accessory when they do. The first time they'd left at dawn he'd spent half the morning with his heart in his mouth. Summoning Derek to the Tower in full daylight was out of the question, but he never had managed to get Derek to clarify exactly much of a heads-up he needed to get away. Then, an hour later, while Stiles was on his way out to the woodpile, he'd caught a glimpse of Derek in the woods, lurking just beyond the edge of the tree-line. He hadn't said anything to Stiles – just grinned the grin of a man sharing the world's most nefarious private joke, then vanished away into the shadows – but he hadn't particularly needed to say anything more. Stiles got the message loud and clear. 

He'd made it back to the Tower that day with his heart in his ears rather than his mouth, and had to work hard at keeping himself from grinning so widely that everyone he saw would know he was up to something. So help him, being able to give the hunters the run-around on their anti-Derek crusade is _fun_. After all the trouble they've put him through keeping Scott's secret ever since the poor guy was turned, this part is very nearly more viciously satisfying than even the _sex_ he's getting out of the deal.

Stiles knows it's got to be too good to last – _something_ here isgoing to have togive eventually, but Derek's not going anywhere and the hunters aren't just going to give up. It's no secret that what they reallywant is permission to throw Stiles into the saddle for the next hunt so they can make him play human-compass five times a day until they find their mark. If any of them cared enough to ask Stiles' opinion, he'd have gladly told them that was a whole lot of wishful thinking, considering that even after weeks of practice, he still can't make the trick work consistently any time between the twilight-hours of sunset and dawn – and doing it even _once_ a day takes it out of you. He'd be less eager to admit that what really scares him is the possibility that maybe it _will_ work – though that's much of a moot point when, again, it's been made clear to him that no-one cares about his opinion. You don't know until you're tested, says Chris Argent. Words to live by. (Stiles wonders how Chris would feel about letting Stiles 'test' how well Chris might deal with being stabbed repeatedly in both legs.)

Fortunately, the other reason why no-one wants to discuss Stiles' concerns is that the hunters have yet to get their plans for him past the very firsthurdle, which is getting Lydia's permission. Since recovering from the first incubus attack she's been none too pleased about the idea of the hunters leaving her undefended for more than hours at a time, and if anything, she's even _less_ pleased about letting them take one of her few remaining servants with them. 

Stiles is so grateful he'd just about forgiven her for the whole Jackson thing within _days_. 

In the meantime Stiles is still getting regular, mindblowing sex with a confusing, incommunicative lump of an incubus, while living an awkward double-life as a castle servant and/or demon hunter informant. If it all blows up in his face a month from now... well, at least he's got some excitement to look forward to. But a month in, the greatest surprise to come out of it is that on the balance of things, Derek is actually _solving_ more problems than he creates. 

And for the record, no – ridding Stiles of his inconvenient virginity doesn't count; the part that counts is Derek's help in solving one very particular problem which has been hanging over his head ever since the day Scott was turned. Derek doesn't get to come out smelling of nothing but roses after this one – it's his presence that forces the issue in the end. But even so, the fact remains that Stiles hadn't made one lick of progress on his own, not from the moment Scott was bitten right up to the day Derek shows up in his room to find his path blocked by a ring of mountain ash around Stiles' bed. 

Derek hits the barrier before he sees it. He looks down, unimpressed in that special way only Derek can be. "This is your idea of a joke?"

Stiles can't resist a little victory bounce. "It worked! It did, didn't it? You can't cross, right?"

"Yes, Stiles," says Derek, with nothing like real patience. "That's how mountain ash _works_."

"Sure, but I didn't know I could get it to work on _you_ until I got you here to try it," Stiles bounces off the bed and puts his toes right up against his ash line, so that Derek's hardly inches in front of him and can't do a thing. He's never had any objection to Derek touching him before, but anyone would get a kick out of having the power to draw the line so firmly. "And you didn't even know it was going to be there, right? You got that I wanted you here, but you didn't know what for. Your mind-reading trick _does_ have blind spots, huh, Derek?"

"Next time I'll be sure to pay more attention," says Derek in a tone like acid, and turns on his heel. 

"The hunters want me to put it around the whole _tower_ ," calls Stiles, before he can get to the window, "and I don't have a good excuse to tell them no."

Derek stops; turns halfway back around. "The whole tower?"

Stiles gives him a shrug. "Apparently woodcutting really is a vital hunting skill. Maybe it's traditional, I don't know – goes along with stalking little girls in red. A month ago, we didn't have enough of this stuff to surround a _table_ ; now they're hauling it in by the log load and grinding it all down." He breaks a gap through the ash with a toe – a peace offering, of sorts. Great as it is to get a rise out of Derek, that's honestly not what this was about. "I thought... maybe if it didn't work on you, that'd be something. It _definitely_ works on Scott, in case you were wondering."

"The werewolf," Derek supplies. 

Stiles nods. "Tested him already. Don't get me wrong – it's nice to know I can keep out things like you if we get any more unfriendlies turning up, but what I really need right now is a way to make it _not_ work without the hunters noticing. I was actually kinda hoping you might have some clever way around it."

Derek's gaze drops again to the thin curve of ash tracing the outline of Stiles' bed, barely distinguishable from the floorboards, his mouth pressed into a thin, hard line. "What if I did?"

* * *

Laying out a ring of mountain ash is one of the oldest and easiest tricks of the trade. Deaton taught him the theory years ago, but before Scott was turned, Stiles never had much interest in wasting his time on rituals he didn't need and couldn't even test – and afterwards, the _last_ thing either of them wanted was the hunters noticing Scott couldn't leave the tower all of a sudden. For months, Stiles has reassured himself with a long list of good reasons why putting a protective ring around the whole tower would be a waste of effort. The nearest source of good mountain ash was a day's ride away, not counting transport time back again. It wouldn't last long enough to be worth the trouble – even magically placed circles of fine woodchips will fall victim to the elements eventually. They didn't _need_ it, as long as they still had stone walls and locking doors. No wild wolf would ever bother breaking in here. 

None of which was going to keep the subject off the table indefinitely. Stiles had never had any solution better than breaking the circle discretely after placing it and hoping the hunters wouldn't notice – and none he could get past his conscience now, knowing that Lydia had been attacked once already. 

Not until Derek brings him a book that teaches him that the possibilities of mountain ash are truly more varied and complex than he'd ever imagined. Tuning a circle to let a specific supernatural creature – or two – through, while keeping the rest away is the _least_ of what he could do with this.

"Where did you _get_ this?" Stiles is almost dumbfounded as he pages through instructions for how to construct circles that aren't circles at all; that can be built into walls or across gates, that can work without a complete loop, that can be broken by hands that didn't make them, that will interlock and cascade one to the next as the outermost is broken... he's not going to get _any_ sleep tonight.

"Sure you want to know?" says Derek, testily.

"If there's more, hell _yeah_." Stiles doesn't even have to think about that one. 

"Don't push your luck, Stiles," Derek grumbles, but with the sort of impatience that Stiles has long since decided is more fond than really impatient. Presumably deducing that not even the offer of amazing sex is going to have much hope of distracting Stiles any time soon, he heads for the window. Stiles is so engrossed he's halfway there before he notices. 

"Wait!" Stiles calls after him, " _Thank you_ , seriously. This is _amazing_." He doesn't care that he's grinning from ear to ear, and he cares even less when he gets Derek to smile back at him.

"I have a vested interest in being able to get in here in future," Derek points out, shrugging.

"Yeah, but you didn't have to bring me the whole book."

"No," Derek agrees. "I guess I didn't."

"As soon as I'm done here you are getting _so much sex_ for this!" Stiles yells as he vanishes out the window. 

When tomorrow comes, however, he's having second thoughts. 

The instructions for constructing a Derek-friendly mountain ash ring are pretty simple; there's not much more to it than for the person who laid out the circle to break it somewhere discrete, then seal the gap with a mixture of ash and Derek's own blood (and Stiles does not care how fast anyone heals, that gap is going to be as small as he can make it). He's already done this with Scott; he knows it works. But Scott is _Scott_ , and wolf or not, he's still the same lovable idiot Stiles has known since he can hardly remember when. Letting Derek in, on the other hand – that has a few implications he's only now realising that he might not have quite thought through. 

Standing in a sheltered spot on the tower wall by the last light of the day, with Derek waiting impatiently in front of him, the time for dithering over his conflicted loyalties is officially over. 

"If I do this," he tells Derek, with his pulse hammering in his ears, "I need you to promise me something."

"You're learning." On Derek's lips it doesn't sound much like a compliment, but at least he doesn't sound angry. Considering that Stiles is nearly convinced that 'turned on' and 'pissed off' are the only two states he's capable of inspiring in Derek, that's more than he was expecting. "What did you have in mind?"

Stiles takes a deep breath. "I need you to swear to me you won't harm anyone who lives here."

Stiles has no idea whether this is close to what Derek was expecting, but he's definitely not pleased. "Including the hunters."

" _Yes_. Look. I don't likethem much more than you do, but they're," Stiles scrubs a hand through his hair. "They're trying to do a good thing! Under all the weird obsession, and the crazy, and the bloodlust, they're protecting people from real monsters, probably more often than not! They're trusting me to keep things like you _out_."

Derek's jaw works soundlessly throughout Stiles' explanation. "And if they track me down out there," he says, jerking his head toward the forest, "you're fine with leaving me defenceless."

"No, I'm _not_ fine, I just... I can't give the same creature-of-the-night they're hunting a free pass into the tower. We both know that now the ring is in place, they're going to be a lot less careful about how deeply they sleep at night. There's letting you in, and there's handing you their heads on a platter."

"You don't trust me." Might be nice if Derek could sound a little more surprised by that. 

"Derek, I don't even know for sure if I can trust _myself_ to know whether I should trust you." Stiles takes a deep breath. "But you could give me a reason to."

Derek huffs and takes a step towards him, close enough to make Stiles very aware of the small difference in height between them. "If you let me in," he says. "I'll swear to you not to harm anyone within the boundaries of this circle, whether they live here or no. _Outside_ your tower, I give you no promises. Will that satisfy you?"

Stiles feels his eyelids flutter closed in relief. "Yeah. That's perfect."

Derek bleeds black. Stiles doesn't know if he'd been expecting that, his head's still buzzing with the enormity of it all, right up to the moment when he closes the circle again and Derek steps over it and pushes him hungrily up against the side of the tower, and soon wipes away all fears this might have become something that would linger between them; that could change where they stand with one another in any way but for the better.

* * *

In the end, everyone wins. Scott and Derek get to keep coming and going as they please, the hunters are happy, and Lydia is... mollified, more or less, and everyone's horribly impressed with Stiles. Except Jackson, but that's business as usual, and Stiles knows even _he's_ happy the hunters can spend more time out hunting again, rather than breathing down their necks all the time. 

It's not all good news that month. Harris is back from his prolonged sabbatical with the start of spring, fresh and eager to resume those parts of his stewardly duties that revolve directly around making Scott and Stiles' lives miserable. A dozen minor chores neither of them bothered with back when they hadn't had Lord Martin's steward breathing down their necks are suddenly reinstated as essential (does anyone _really_ care which flag is flying from the tower in which orientation at what hour of the day, or how long it's been since they last polished the brasswork in the great hall? They're not in any danger of having _guests_ up here these days). Since Scott and Stiles are already responsible for lugging the greater part of the upper floors' needs in water and firewood up every one of the Tower stairs, scraping out the fireplaces, emptying their chamber pots and sweeping their floors – not to mention being expected to pitch in on laundry day now that there's _no-one else_ to help – it's slightly beyond even Harris to make his favourite spiels about their 'slovenly excuse for dedication to duty' all that convincing. Even _Jackson_ seems closer to second-hand embarrassment than his usual gleeful schadenfreude over it lately, and Jackson _knows_ Scott's wolf-muscles are about the only reason they're keeping up at all. Frankly, by any human standards, the workload the Tower's last two dedicated chore-boys have been shouldering lately should have them qualified for sainthood. 

Stiles reallyhopes Harris himself never gets around to examining the mystery of how they're keeping up too closely. The last thing they need is for Scott to come under extra scrutiny from someone who hates him as much as Harris does, and keeping the man diverted is close to being a full-time job these days. Harris has had it in for both of them for years; bad enough that Stiles is the son of Lord Martin's marshal, whom Harris hadn't liked even _before_ that ugly little incident where his bookkeeping skills had come under suspicion. He clearly doesn't know what to do with the implicit promotion Stiles has gotten himself now that he's assisting the hunters on a regular basis – Harris had to have the instruction repeated to him _twice_ the first time Kate had shown up to demand their share of Stiles' time, and apparently managed to selectively forget the whole experience between that and the second time, leaving Kate to explain all over again. 

For that matter, Harris has never known quite what to do with Lydia either, who on the one hand outranks him, but on the other is young, female, and likely still too inescapably connected to the unpleasantness surrounding the former Lady Martin to be entirely trusted – at least to Harris' mind. Lydia is also opinionated, impatient, and will agree with Harris only just enough to keep him on his toes. The hunters, meanwhile, may not _technically_ outrank him, but remain both important and terrifying enough to throw a fair bit of weight around when they want to (which they usually do). And as entertaining as it may be to watch Harris stuck in the middle of all the posturing going on around the tower lately, it'd be a good deal more entertaining if his default method of coping didn't involve taking it out on any target available.

Stiles' own personal road to hell may well begin the day he caves to the temptation to see if Derek can find it in his demonic heart to do him a favour and murder the guy in his sleep.

Fortunately, Harris has his own distractions, what with the household's annual journey to the manor house on the far side of the Martin estate fast approaching, and no-one is being spared their part in that excitement. Goods have to be packed, horses have to be acquired (read: borrowed from people who'll need them back again later), inns have to be notified (or rather _reminded_ , in no uncertain terms, of the importance of the guests they'll be expecting very soon) and the whole route scoured for winter debris of the sort which might offend a train of wagons trying to get past in a hurry. Since the Tower's guard has been whittled down to only Jackson plus the Hunters – and even Jackson's more inclined to see an armed escort as something he _deserves_ rather than something he has to admit to _needing_ – that's left the hunters responsible for a large share of the scouting and messenger-work. 

Ordinarily, that shouldn't have been a problem. As far as Stiles understands it, this all falls within the terms of their agreement with Lord Martin, which broadly covers the provision of supplies, shelter and lordly endorsement on the part of the Martins, in exchange for which the hunters are expected to dispatch assorted creatures of the night, inconvenience the local bandit population, and generally remind the peasants that their taxes are due whenever the opportunity might present itself. That charter has apparently been broadened recently to keep them operating in the lord's absence – Stiles is even hazier on those details, but protecting the household while the rest of the knights are away was presumably a significant theme. Even so, being expected to put that part into practice would probably have gone down better with the hunters if not for the lingering issue of that rogue incubus they've been hunting, still out there besmirching their spotless strike record. 

And even after more than a month with nothing to show for it, the hunters have no trouble keeping themselves busy on that front. Besides periodically calling Stiles down and charging away in whatever direction he points them at, hunting the incubus seems to require a lot of riding around to liaise with other hunter teams in adjacent regions, plus some sort of general community outreach effort to whip all the local peasants into a state of panic over the matter (and probably remind the little people about their taxes while they're at it). If Chris and Kate had hoped that Lydia might be a bit less obstinate over the division of their time (not to mention _Stiles'_ time) now the Tower's defensive barrier is in place, by now they must be thoroughly disappointed. 

Stiles is in no way qualified to guess how much of that friction is real disagreement and how much comes down to personal issues and spite at this point, but either way, the excitement of internal Tower politics _never_ lets up. 

This is all to say that, even a solid three weeks after the mountain ash went down around the tower, it's no surprise for Stiles to make it into the grand hall at dinner time (late) to find that Lydia and Chris are already arguing. And just as naturally, it's Harris who spots him first. 

"Mr Stilinski," calls Harris. "I can only assume this delay means I can expect to find the heraldic tapestries have finallybeen dusted when next I check." He holds up his mug expectantly, still far too important to stoop to pouring his own ale. 

Stiles mutters something uncomplimentary on the subject of drapery, and hurries over with the jug, generally concluding that whatever Scott's eyebrows are trying to communicate to him from the other side of the table probably isn't all that important. Actually, he'd been pestering the cook for anything she could remember about the messenger who'd arrived earlier with the letters from Lord Martin's men – something which must have taken weeks to weave its way back along the supply lines – so Stiles could track him down and find out why there'd been nothing from his Dad. There'd been no notice of death in those messages, so he isn't panicking (yet), but he's been waiting for that letter ever since the day his Dad left.

Unfortunately, Chris is the one to come to Stiles' defence. "You shouldn't be so hard on him," he tells Harris, interrupting his 'discussion' with Lydia. "That boy has better things in his future than manual labour. We should really see about setting aside some more time for his studies, wouldn't you agree, Stiles?"

"I'd find it hard to see much future in his studies if a little dusting is still beyond his means," Harris returns, pointedly.

Across the hall, Stiles catches Jackson rolling his eyes; it's the sort of sentiment he'd agree with emphatically if it wasn't for how Jackson would be the first one here to abandon him in the same boat as everyone else here. If they really have to argue over dinner, Stiles rather wishes they'd all leave him out of it.

"With all due respect," says Chris, in that particular tone which means quite the opposite, "one could hardly expect a steward to know what to look for in a case like Stiles'. Speaking of which," he adds, turning back to Lydia, "we've still not settled the matter of when Stiles will be joining us out hunting."

"Hadn't we?" says Lydia, sweetly. "I could have sworn you'd asked me weeks ago, and I'd informed you the answer was 'no'."

"And now that we have the mountain ash in place, I'd say the time has come to revisit the subject," Chris replies, smooth as anything, not at all deterred that he's doing this without backup. Both Allison and Kate are out on the hunt tonight – or maybe just on some errand; Stiles doesn't really keep track. Heck, maybe that's what they were arguing about when he came in. 

Lydia affects one of her most elegantly put upon expressions. "Am I to understand, Mr Argent, that your ash can be expected to aid in the packing and cleaning chores in Stiles' place, while he's unavailable?"

"The _packing_ and _cleaning_ can safely be delayed for a matter of days in the name of eliminating the demon terrorising your countryside!" Christ snaps back, with a force that makes Stiles wince slightly.

"How many days do you think that might that be, exactly?" Lydia inquires. "I do believe _someone_ had assured me that when he could dedicate his men to the task, the demon would be lucky to outlast their very next expedition. How many trips ago was that?"

"My _men_ have been split between hunting and playing messenger for trivialities!"

Lydia delicately examines the chunk of potato speared on the end of her fork. "Remind me, Mr Argent, _how_ many victims has your demon claimed in that time?"

"We may not have been made _aware_ of any known victims-"

"And how many times has it been sighted since your sister's fateful night?" Lydia cuts him off without raising her voice. Apparently interpreting Chris' expression as a negative, she ploughs on, "So, let me get this straight. You want _me_ to postpone our travel to the manor house, _and_ lend you the use of one of my few remaining servants, so you can gallivant off across the countryside hunting for a demon – which for all we know may have left this part of the country weeks ago – while I sit here in the same room where _I_ came under attack from a real demon – one that I might remind you was dispatched without any help from your hunters in the first place. I'm simply to cool my heels here until such time as you find convenient. Why don't I think about that... hm. _No_ ," she pronounces. 

Chris opens his mouth. 

"Now surely we can find more _pleasant_ topics for dinner conversation?" Lydia declares, before Chris has gotten out a first syllable. "Jackson, wasn't there a letter for you today? From Danny?"

"Oh, don't let me interrupt," Jackson mutters around a lump of mutton. "But if you wanna know, yeah, I did. The skirmishing has been agreeing with him more than all the waiting in between. Wishes I was there."

"Is that so," Chris begins, and Stiles can practically _see_ him gearing up to ask Jackson just what it's like to be hearing about the action from his perspective, as the guy who got denied the right to go along – when, to his immense relief, Allison picks that moment to march into the hall out of nowhere, still in her riding clothes, her countenance equal parts determined and spooked. 

"Home early aren't we, Miss Argent?" Lydia calls, obviously as surprised as any of them.

Allison barely gives her a sideways glance. "Excuse me, my lady. I need to speak with my father. _Urgently_."

Chris is already on his feet; he meets Allison halfway across the hall and a couple of minutes of tense, hushed conversation ensues. Stiles can't make out a word of it, but he does get to watch Scott's eyes widen steadily through the whole exchange. 

Chris turns back to the table with an air of practiced condescension. "My apologies, Miss Lydia, an urgent matter has arisen and I fear I'm forced to leave you to finish your meal without my company. Word has just reached us that the incubus has claimed _another_ victim." 

There's absolutely no missing the undertone of victory in his voice; for a long moment after the whole room goes completely silent.

Stiles only vaguely remembers watching them leave, or much of anything else that happens over dinner that night. 

* * *

It's hours before Stiles has the chance to get away from his chores and lock himself in a room alone. He's not going to call Derek; he can't afford that until he's at least had the chance to calm down, but the truth is that, somewhere on the inside, he knows he's been waiting for something like this to happen for weeks. He hates the hunters for their smug sense of certainty – _one_ mysterious death and _of course_ the incubus has to be the one to blame. He hates Derek for putting him in this position; hates himself for doubting Derek, for not being able to snap his fingers and know exactly who to trust. Hates most of all that little part of himself that just doesn't want to _know_ whether Derek's involved, and hates that he's going to haveto _ask_ , even knowing he's not going to be able to believe the reply. 

Going by the way he's feeling right now, he's not going to be in any state to deal with Derek until this time tomorrow at the earliest. But when he hears Derek's voice above him say, "I'm not going to like this one, am I?" it's such a non-surprise that Stiles doesn't bother looking up right away. 

"I'm gonna have to revise my theories on how much you can read from me if you think I want you here right now," he mutters, trying to bury his face in the pillow.

"You don't _want_ to want me here. Not quite the same thing," says Derek. "But you do want answers to something you don't think you're allowed to ask, and it's tearing you up."

Stiles knows putting this off isn't going to make it any better. He sighs, rolls over and sits up, needing to be able to look Derek in the eye while he does this. "The hunters say they found your latest victim."

A rush of different emotions flash across Derek's face, too fast to catch, before settling on understanding. He makes a noise like a sigh that goes through his nose. "You mean they found someone dead, without obvious cause, and they think it was me." He looks to Stiles. "Who?"

"A woman from a town south of here. Perfectly healthy until yesterday; this morning, she's dead."

"Looking like she died in her sleep?" asks Derek.

"No, like she died in agony while having the life sucked out of her, what do you think?" Thank _you_ , Scott, for all the gory detail the rest of the room wasn't supposed to hear. 

Derek stares at him a moment. "You're not joking."

"Ha, yeah! Funny subject!"

Derek breathes out. "Then it wasn't one of us."

"What?" Apparently Stiles has missed something somewhere. 

"When we kill," Derek explains, "it's painless. It wouldn't... your hunters should _know_ that."

"Well, how am I supposed to know?" Stiles is almost yelling and he doesn't even care. "Maybe they're just telling each other she died horribly because it makes a better story!"

The look Derek gives him then is all but unreadable, and not in a good way. "You think I did it."

Stiles deflates a bit, and sighs into his hands. "I don't know what to think, okay? What do I know – just because you haven't sucked the life out of me doesn't mean you don't need to suck the life out of _someone_ once in a while. It's what your type are known for and all."

"Stiles," says Derek, obviously losing patience, "I don't – look, for one thing, if I did, don't you think I'd have the sense to pick someone further away? And for another, we don't suck life out of _anyone_. It's not even about life, it's about... _sensation_."

"Sensation," Stiles echoes. This is officially all the information on the subject Derek has ever offered him.

Derek nods, absently. "The more intense, the better."

Stiles thinks about this. "So. Sex and death, huh?"

"The most intense sensation humans can experience," Derek agrees. "When we touch you, we feel some of what you feel. We need that. Without it... there isn't a good word for it in your language. Our bodies forget how to feel. We go numb to pain, then to contact, until eventually we can't feel our own fingers. We become disconnected from our physical form to the point that control is like pulling puppet strings from a distance. The paralysis spreads until it kills us."

Stiles is starting to feel he should be writing this down. "So," he says, thinking aloud, "the intense second-hand sensation of death isn't intensified even further by, say, really intense _pain_?"

Derek actually winces. "Pain doesn't help. It has the opposite effect; it uses up our reserves, makes us _want_ to forget how to feel and accelerates the process. The sensation has to be pleasant or it doesn't work."

"Dying is a _pleasant_ sensation?"

"It can be."

For once in his life, Stiles lets his eyebrows handle this one.

Derek makes another impatient noise. "It's hard to describe. It's about release; moving beyond pain, going somewhere you can't ever be hurt again. What we'dfeel ourselves if we gave in to the temptation to let go. Some of us find it intoxicating; even see it as a mercy."

_Jesus_ , thinks Stiles, scrubbing a hand over his face. It's not that he doesn't understand that, it's that he's not sure he wants to. "I think I liked the life-sucking explanation better."

"You don't believe me." Derek doesn't sound hurt or indignant about this, just resigned. 

"I _want_ to, not that I like what that probably says about me, when you're, you know..." Stiles waves a hand in Derek's general direction. "But how am I supposed to know when I've only got your word for it, and none of my books say anything like this?"

"These are the books that told you I'd keel over at the touch of another man?" says Derek, because clearly they're way past their sincerity quota for this conversation already.

"Ha, funny. I'm talking about my bestiary, smartass," says Stiles, tossing a pillow in Derek's direction. "Pretty sure that's one's more reliable than some poet's one-handed-fantasy."

"This isn't in your books," says Derek, speaking very slowly and clearly, "because this _isn't_ information we share with just anyone. You think we _want_ every hunter in the country to knowour greatest weakness is _extreme pain?_ "

Stiles frowns. He can't really argue that, but something here doesn't feel like it adds up and he can't quite put his finger on what. "Instead of – wait, Lydia!" he exclaims, finally hitting paydirt. "She told me the real version of that story! You explain to me how _that's_ supposed to work without life-sucking, mister."

Derek's brow furrows inwards. "Which story?"

"The one where they fed poison to some poor kid and left him as incubus-bait? This ringing any bells?"

Derek looks at him blankly. "What part is it you don't understand?"

"How about how the boy lived if the incubus didn't _suck the death_ out of him, or whatever you wanna call that part?" If Derek's being deliberately obtuse Stiles is not going to forgive him in a hurry.

Derek's frown only deepens. "Stiles, no-one in that story lived. The poison paralysed the boy and left him to die slowly in horrible pain. When the incubus touched him, it was the _pain_ that left it helpless. I just explained this to you."

"That's not how Lydia tells it."

"Then she's either mistaken or _lying_." Derek bites out the words. 

"Mistaken? _Lydia_? And why would she lie to me about how she knew I was lying unless... _oh my god_. Lydia, you _evil_ – you evil _genius_."

The noise Derek makes this time is a real sigh, no quantifications involved. "She fed you a line to test you, and you bought it, didn't you?"

"She _knows_ I was still lying to her," Stiles says, thinking aloud through his rising horror. "And she hasn't pressed it because... god, she must know about the geas too. She probably recognised what it was as soon as I passed out." He looks up at Derek through his fingers. "So what does she _think_ is really going on?"

"At a guess?" offers Derek. "Probably that you killed that incubus by summoning something worse and making a deal you shouldn't have."

If so, that means she's giving Stiles _way_ more credit than he deserves, but Derek's guess is as good as any Stiles can come up with. Everything Lydia has done to keep the hunters off Stiles' back over the last few weeks is suddenly starting to look way more significant; Stiles can't believe he fell for thinking she was ever as clueless about what's really been going on as she'd let them all believe. "Do you think she knows the something is our other incubus?"

"You tell me," says Derek. 

Stiles puts his head in his hands. "You know," he gripes, "none of this would be an issue if you'd helped me come up with a better cover story when I asked you to."

Derek rolls his eyes. " _Clearly_ I should have known better than to trust you to come up with a convincing story on your own."

"Hey! I don't know if you've noticed, but I'm not _actually_ as qualified for this as everyone thinks I am!" The petty side of Stiles would really like to suggest that Derek just never imagined the fallout was going to become his problem until after the Kate Fiasco, but they're not going to get anywhere useful by sniping at each other all night. 

Derek glares at him, but given how he passes up the obvious opening for further insult against Stiles' intelligence, maybe he's reaching a similar conclusion. 

Stiles rubs his hands over his face one more time and tries to think like someone who actually does have more than a snowball's chance in hell of sorting his life out in the foreseeable future. "Okay," he says. "Let's say I'm going to believe you on this one for now. We need to find out what _really_ killed that woman." Looking Derek right in the eye, he finishes, "And then we need to find a way to fake your death."


	6. Chapter 6

Riding does notagree with Stiles.

Allison must have been just about born in the saddle, knowing the Argents. Jackson and the rest of the knights-to-be would have started learning to ride not much older than her. Lydia, being Lydia, naturally rides with the same accomplished ease that comes with everything else she does, suitably ladylike or otherwise. Even _Scott_ has somehow gone and redefined 'ordinary stableboy' such that it includes 'decent natural horseman' in its skill set – when the opportunity comes up, that is, which isn't nearly often enough to give Scott the excuse of having ever had much practice. And if his best friend's embarrassingly natural ease in the saddle wasn't bad enough, there's no way Stiles' father would make much of a marshal without being able to handle a horse with the best of them, and he's held that job as long as Stiles can remember.

No, it's just Stiles who has to go and prove that 'naturally competent rider' isn't an inheritable trait. Chalk down yet another point on his expanding list of Reasons Why Sending Stiles Out With The Hunters Was A Terrible Idea.

"Need some pointers?" Kate's voice startles him half out of his skin; he must have completely missed her spurring her own horse out of her place in line behind to sneak up beside him.

The odds that a few pointers from Kate are what he needs to turn this around really don't seem all that promising. "No, I think we're good here. Aren't we, girl?" Stiles gives his horse a friendly pat on the back of the neck, and gets no reaction whatsoever for his trouble.

Kate leans in conspiratorially close. " _Boy_ ," she whispers. "Oh," says Stiles. Someone had probably told him that earlier. "Uh."

" _Relax_ ," suggests Kate. "The idea is to move _with_ the horse; don't stiffen up so much. There's no need to hold the reins so tight – give him his head, he knows to keep following the guy in front – at least until things get interesting."

"Interesting," Stiles echoes, though he really should know better.

"This hasn't been quite the non-stop excitement you were expecting from your first real hunt, hey kid?" As usually, Kate makes 'kid' sound like an affectionate title for a twelve-year-old. "Galloping off after wolves in the woods as they dart and flee before you, sniping with the bow from horseback – a good hunt'll end that way, but first, you've got this part: long, slow and boring. It's usually _just_ when you're settling in that everything changes. People forget werewolves aren't just dumb animals. The smart ones will wait, then come at you from upwind, and they know _just_ how to startle a horse into rearing." She gives him a toothy grin. "Ease up on the reins, Stiles. It's your kneesthat'll keep you on when a mouth full of fangs bursts out of the woods at us." Kate gives his horse a friendly pat on the rump, and falls back behind him again.

Stiles decides she's still jealous about how _he_ could get the magic dagger trick to work and she couldn't. "Thanks. I'll remember that," he mutters, doing his level best to forget.

The truth of how much of the next couple of hours he spends with his knees clenched like a human vice is something Stiles will take with him to the grave.

* * *

Whether Derek appreciates his genius or not, Stiles is very proud of how fast his plan to solve their hunter problems had come together. If pushed, though, he might have to admit he'd have been happier if he'd come up with a way to make it work _without_ forcing himself to spend so many days in the wilderness on an uncooperative four-legged animal. Or if he'd been able to put it into action without first putting himself through yet another confrontation with the inestimable lady of the tower.

Lydia takes his request with as much grace as could be expected. "Now you _want_ me to send you out with the hunters?" she echoes.

"Yep, that's pretty much the thing I just said," says Stiles, rocking on his heels.

The worst part about doing this is knowing that _she knows_. She knows he's lying to her. She's almost certainly figured out _why_ , and even if Derek's right and what Lydia _thinks_ she knowsis a long way short of all true, that still leaves Stiles steering this conversation on the gale winds of insinuation, navigating the narrow between the sirens of polite fiction and the cliffs of his next magical blackout. There's a real possibility that the only thing keeping her from going straight to the hunters to report him for consorting with agents of evil is that she thinks he saved her life that night (which is _so far_ from true you could structure a three-act comedy of errors around it) or she's worried the fallout could come down hard on everyone'sheads if this gets out (which... actually may not be entirely wrong). He feels like a guilty kid trying to explain away his latest childish misdemeanour to an increasingly skeptical father all over again.

Being indirect isn't a skill Stiles has ever mastered. Even writing himself a script and memorising it word for word barely gets him past the introduction. From here on in, it's going to be up to him to improvise.

"And I'm to understand you experienced this sudden change of heart because...?" says Lydia.

Stiles watches her drop a new stitch into place with a sharp tug of her needle, reminded none-too-subtly that he's sharing her attention with her embroidery wheel. "Well, they're not going to stop _asking_ , and with all that's happened, I feel like I owe it to everyone to give this a try, you know?"

" _Before_ the hunters stumble over their next body?" offers Lydia sweetly, making him wince. He's got no way of knowing whether she buys the story that Derek was responsible for that poor village-woman's death – even _Stiles_ is closer to the fence on that one than he'd like to be – but it can't be sitting easily on her conscience if she does.

"Well, soon would probably be good, yeah," he says, doing his best at playing it cool. This is more or less working for him right up until Lydia flicks one pointed look his way, and he caves on the spot. "I don't... look, I'm not gonna pretend I really know what I've got myself into with all this, but if what we're planning works, we could put an end to this. No more guilt-tripping over dinner, no-one else has to get hurt." It's the truth, if only by a few convenient technicalities.

"And it's all just as simple as that?" says Lydia. "You ride out on one trip, help the hunters take care of our demon problem, and then we can all get back to our lives without ever having to worry about all this again."

Still hanging off the last of that guilty impulse to be as truthful as he can realistically manage, this last part gives Stiles a little more trouble. "I couldn't really make any promises-"

" _Stiles_ ," Lydia interrupts, "maybe you didn't understand me. I don't know what you did, and I do not _want_ to know, but I _cannot_ keep covering for you indefinitely. Whatever this is costing you, _sort it out_. Are we clear?"

Stiles realises he's gaping at her and shuts his mouth with a click. "Clear as crystal," he stammers.

Lydia gives a long, put-upon sigh, relaxing back into her chair like Stiles hasn't just forced her to hang every unspoken rule of this engagement by the throat until it cooperated. "Well, if you must, I suppose the packing can wait a few days," she declares. "I'll have a word with the hunters, and by this time next week, all this trouble will be behind us, yes?"

Being Lydia though, she waits until Chris makes his next attempt to convince her over dinner before she 'grudgingly' relents to allow one of her servants accompany him on his next hunt.

"Provided you don't plan to leave me short-staffed and the tower unguarded for more than two full days, of course," she finishes, and Stiles actually drops the empty mug he's holding and barely catches it before it hits the floor and everyone in the hall hears it. What is she _doing?_ No matter how bad she wants this over with there's no _way_ he can get this done with only a two day ride!

Across the hall, Chris looks about to have the same reaction (minus mug), and almost certainly would have if Kate hadn't put a hand on his and leant across to take over.

"The thing about demon hunting," Kate says, to Lydia, "you can't really make it happen on a schedule. But what we _can_ do, if you're amenable to doing us a sort of trade, is leave one of our own behind. You get your guard, we get to take our time. Fair's fair."

The two women exchange smiles that might charitably be described as 'wide and pleasant'.

"Then I believe we have an agreement," Lydia declares.

"See, big brother?" says Kate, "She's not unreasonable. A little polite negotiation will get you everywhere. All we have to do now is decide which unlucky hunter's going to miss the big moment."

"We could ask for volunteers," says Chris, only a little stiffly, "but I'd recommend Bennet. He's-"

"I want Allison," says Lydia.

The two older Argents stop and stare at her.

"Oh, did I say 'want'?" says Lydia, "You're going to leave Allison here, or none of you go."

"Far be it from me to place doubt upon the skills of my own daughter," says Chris, in a teeth-grinding tone that suggests it's about take a lot more than sisterly interference to hold him back, "but I would _strongly suggest_ that one of our more experienced men would be appropriate."

Lydia gives him a look that is far too innocent for someone who just elected her own best friend as her personal bodyguard. "Why, Mr Argent, am I to imagine a young woman like your daughter might have cause to feel herself less than perfectly safe here within your mountain ash defences while all the hunters are gone? Have I misunderstood?"

There's another of those dangerous silences, but no further intervention becomes necessary before Chris concedes. "Of course not. I am sure my daughter will do admirably here in our absence."

It's a good thing Scott's standing behind Chris while Lydia and the hunters finish sorting out the details of an arrangement which grants him and Allison several days together without a chaperone, because that way Chris _doesn't_ get see Scott's expression when it sinks in. Stiles does, though. He also catches Lydia mouthing the words ' _you owe_ me' to both halves of the happy couple before they all file out of the hall that night.

Yeah, it's official: Stiles' type is 'gorgeous and terrifying'. Lydia is a beautiful, amazing, scheming genius on a level Derek cannot hope to compare to. Her place in Stiles' affections staggers only when it dawns on him that her clever machinations have conveniently sentenced Stiles himself to an unspecified number of days in the presence of both older Argents _and_ all their lackeys, without even Allison to turn to for human company.

Lydia probably arranged that part on purpose too.

* * *

Sleeping rough doesn't much agree with Stiles either. His thin mattress back home at the tower was never exactly luxurious, but a few nights' experience with hunters' bedrolls and he's already sworn never to speak ill of it again. Three days on horseback have left him with aches in muscles he didn't know he _had_ , as Derek zigzags across the countryside and the hunters follow, far from roads and civilisation, pulling them gradually south and west. At least they've spared him from night watch duty; no-one with any sense would have trusted Stiles to stay awake.

The magic wears him inside rather than out, a steady sap on his focus and concentration with every stop they make. It's working more often than not though; Chris has a theory the spell becomes easier the closer to their target they get, and the hunters spur their horses forward more eagerly each time Stiles makes the dagger find its bearing. It's not easy, tracking something that can fly, but Derek can't fly high or far in the daylight without being seen, and according to the hunters, an incubus which hasn't been out ravishing the locals every other night or so will wear down that much sooner. Stiles mostly tries not to worry about that part too much.

They get their first glimpse of him on the second day – practically catch him _napping_ in the lee of a huge boulder, barely out of sight. It happens so fast no-one's ready for it; they'd all noticed the dogs had been agitated, but everyone thought it was just another squirrel. Derek is on his feet and in the air before the hunters have figured out what they're seeing. He swoops away over their heads, so low they have to duck as he passes, throwing the ranks into a chaos of wheeling horses and flying arrows. Then Derek's away – the black shape of his wings soaring high beyond the treetops – and the chase is on, Chris at the fore and all his men charging along behind him.

They never did get so far as discussing what Stiles was supposed to do at this part beyond 'leave that to us', but he's pretty sure that clinging to the reins for dear life while his horse prances and bucks in the confusion wasn't in the plan. In theory, he knows that some combination of kicking his horse in the side and pulling on one of the reins should get it to turn around, which seems like it ought to be a good start. Throwing a look over his shoulder at the rest of the departing party at the same time, however, turns out to be a mistake. Stiles' horse sidles left and he loses his balance altogether – only to be saved when someone's hand shoves him back up from his blindside.

"Easy there; they'll be back," says Kate, appearing on his right. She's comfortably mounted and apparently not in a hurry to go anywhere.

Stiles waves a hand at the departing riders. "Aren't we supposed to...?"

Kate slaps him on the shoulder. "We'll make a horseman of you yet, little magician, but for now, leave the chase to the real men."

This is obviously as nice a way of saying 'we don't want you falling off your horse and getting in our way' as any of them would've given him. "You're not gonna...?" Stiles gestures again in the same direction.

"Someone's got to keep an eye on you," says Kate. "We wouldn't risk you out here if we didn't have a plan to keep our little magician safe."

"That's... _nice_ of you," says Stiles, working hard to reconcile this with what has until now been the overwhelming impression that Kate's interest in his welfare starts and ends with how useful he is.

"Of course," says Kate, "Watching out for the weak ones is what hunting's all about," which makes no sense. _Hunting_ is what hunting is about. They're not even going to need Stiles again if they bring Derek down now, why would she miss her chance?

That's when it clicks.

"Oh my god, you think he's going to double back and go for me," he exclaims, "If he takes me out the rest of you are lost in the woods!" If Stiles had been nearly as scared of Derek as he's meant to be, he'd probably have got that a lot sooner.

Kate makes a show of looking around for listeners, then leans in, pitching her voice the way an actor pitches a stage whisper meant to carry all the way to the back. "Word to the wise: demons have _supernaturally_ goodhearing. I wouldn't talk about it quite so loud if I were you."

Kate likes making him nervous: this is hardly news, but that's not all that's going on here. She _wants_ Derek to have heard him. Stiles isn't just their guide, he's bait for an _ambush_.

Good thing that getting ambushed by a mad demon is the least of his worries right now.

Stiles holds onto the hope that Derek _meant_ to be seen – it wouldn't be such a dumb idea to give the hunters a glimpse of the prize along the way, to make Stiles' long trail of breadcrumbs that much more convincing. He hopes the look of shock on Derek's face when he saw them was a sign of good acting, and that he has an equally brilliant plan to evade the hail of sharp, flying objects on his tail until he gets the chance to give the hunters the slip again. It'd be nice if Derek had given Stiles reason to have that much faith in him, but the best he feels he can realistically hope for is that Derek won't _actually_ make his Kate-mistake twice.

When the rest of the hunters do reappear, though, their faces tight with failure, the wave of relief turns out to be not so hard to hide after all. Somewhere on the inside, he supposes he'd never really imagined Derek would go down so easily as that.

* * *

By and large, moments of excitement are even rarer than Kate had promised him, which leaves Stiles with plenty of time to wonder about things like how incubus hunts are even supposed to work when they don't have a convenient bloody dagger to point the way. The dogs have something to do with it – you can't track demons by smell, as he understands it, but some animals have a sixth-sense-way of telling when something wicked lurks nigh – once you get them within the range of 'nigh', which remains more of a sticking point. From what little the hunters will tell him, it sounds like lying in wait by the bedroom door of a likely victim would usually be a major theme, and Derek's refusal to go after local peasants has caused some a lot of hunterly consternation.

He hasn't yet mustered the stones to go to Chris or Kate directly to ask whether 'died in horrible pain' truly is such a classic feature of incubus-victims as they've let everyone believe. He'd got Allison to agree to look into it for him just before they left though, when he'd brought up his concerns that there might be something else out there. He hadn't even had to lie very much to her – it was true that none of his limited sources mentioned victims who died in agony, though the rest of the truth was that Stiles' books didn't say much of anything on the subject either.

Allison had come back with her lips pursed unhappily; the hunters' sources spoke of victims being sometimes found in states of 'sexual disarray' or with expressions of ecstasy on their faces. There was no mention of agony. The older hunters were content to brush it off or imply that perhaps it signified a demonic attempt to hide the murder. Agreement seemed to be that just because a demon could make your final moments ecstatic didn't mean it _would_ – especially if it knew there were hunters on the look out for it already.

Stiles tries out the idea that Derek's reaction to the news of that woman's death had been not that of the innocent wronged, but of the criminal whose cover-up had failed. It doesn't sit that easily with the Derek he knows, but Stiles is wise enough to recognise he's maybe not the world's least biased judge at this point.

He really wishes he'd been able to wait for Scott to get back before leaving.

* * *

The trouble with getting information out of Derek doesn't begin and end with his stubborn aversion to providing straight answers – he'll give them occasionally, if Stiles pushes hard enough. The problem is that the answer to almost any question that starts with, "is it true that...?" or, "can you really...?" will be a negative – the kind of negative Derek can't prove or demonstrate. Stiles doesn't feel like he's learning very much.

"So I was reading back through my bestiary..." he begins, late one night, not long before his first great hunting expedition would put an end to these evenings for a while.

"Oh, here we go." Derek has his hands under Stiles' tunic, his nose nudging the fabric up over his hipbone – he's taking his time getting Stiles out of his clothes tonight, and he doesn't look up. It's possible Stiles' efforts at information gathering would go down better if they didn't happen when Derek's trying to have sex with him, but it's not like he gets a lot of time around Derek otherwise. He's just working with what he's given.

"Is it true you can really take 'any form your victim desires'?" Stiles asks, "Because if you've been holding out on me – I'm just saying, we need to talk about this."

"Can I..." Derek echoes, breaking off like he can't even bear to repeat the rest. "Sure," he says, and Stiles does _not_ miss that eye-roll, though he also doesn't miss the improbably sinuous movement that ripples up Derek's spine as he shifts his upper body into the candlelight, barely out of reach. "How's this form work for you?"

Nearly half of Stiles wants to say, "Do that again," but it gets narrowly beaten out by the part that rooting for, "Could be better if it wasn't _avoiding my question_."

Derek gives him a look that goes on slightly too long, then looks down at himself with one of those smiles that always means trouble.

"Stiles," says Derek, crawling languidly up his body, "if there's someone else out there you'd rather take to your bed," he goes on, drawing a leg between Stiles' thighs as he moves so his weight slides downwards and in, just so. His voice drops to a whisper, "I'm not stopping you."

No, not stopping him: just casually inviting Stiles to rut against his leg until he comes with his pants still on or gives in and begs for more. Derek is a rotten, _rotten_ tease: the prosecution rests its case.

"C'mon, Derek," Stiles manages – pleads, maybe, "I thought we were done with the evasive answers."

Derek huffs, losing patience, which (to Stiles' inescapable disappointment) also translates to shifting his weight elsewhere. "If we could take the form of any human we chose, do you really think we'd waste it playing out people's fantasies? Wouldn't the hunters have warned you about something that important?"

Stiles is taking that to mean that if it _is_ true, the hunters _don't_ know, and Derek doesn't entirely trust him enough to keep it that way. "If the answer's 'no', you could just _say_ so."

Derek gives a long, put-upon sigh, and rolls onto his side, out of Stile's space. "I could probably make a human _think_ I was someone else if I had them deep enough under my thrall," he admits. "Not something I've tried."

Victory for the inquisition, but not so much for the odds of getting an orgasm sometime tonight. Stiles pushes himself up onto his side, drops his hand on Derek's hip and uses it to pull himself very deliberately into the gap Derek had put between them. "Yooooou could try it on me?" he volunteers, looking up at Derek with a grin. This is more or less what passes for flirting when you're dating a demon.

"And I'd want to do that because...?" says Derek, as accompanied by Derek's Eyebrows.

Stiles edges himself closer and lets his hand wander a bit. "C'mon, aren't you a _little_ bit curious?"

"No," Derek says firmly, then, rather less firm, "Besides, I couldn't put you under my thrall now if I wanted to," follows, all in one breath.

This much is news to Stiles. "Why not?"

Derek props himself up on an arm. "You know what the thrall is, Stiles?"

Stiles doesn't, not beyond the very basics, and Derek had better believe he's taking detailed mental notes on anything Derek will give him. "I know it put Lydia in a coma for twenty four hours."

"That's what it can _do_. I'm asking if know about what it _is_." Derek catches Stiles' wandering hand in his own and pulls it down between them. Right. Talking now. Stiles can do that.

"It's..." A few sections of unhelpful flowery prose from That Poem come back to haunt him from the far reaches of his memory. "It's a state that takes away your free will, right? Or... your will to disobey?"

"Closer," says Derek. "But it's a little more intimate in practice. You see, Stiles," he goes on, as he begins to rub circles into the inside of Stiles' wrist with his thumb, "everything that makes it possible to put a human under my thrall comes from the all-consuming desire to _have_ me. _Will_ becomes secondary to desire that runs that deep. Anything I asked, anything I wanted you to believe, you'd do for me – all for no more than the promise that I _might_ eventually give you what every atom of your being is telling you that you need."

And this? Would be what passes for dirty talk. Stiles couldn't honestly say the combination isn't kinda working for him.

"As you might imagine," says Derek, "it's easiest to inspire that sort of need in desperate virgins – or the unhappily married. Virginity can be a more persistent state than most people think."

"So, like, you're still kind of a virgin for magical purposes if you've never had _really good_ sex?" If so, Stiles gets to enjoy the smug assurance he got himself cured of anything resemblingmagic-virginity the night Derek crawled in through Lydia's window.

"That's the idea," Derek whispers, tracing the line up the inside of Stiles' forearm. "The thrall runs on _anticipation_ ; the build to that one perfect moment only I can give you." There his thumb stills, and he gives Stiles a look. "Assuming, that is, I choose to give you anything at all."

That last part sounds awfully like a real threat. "Hey, last chance you're gonna get before the hunters start playing round-the-clock chaperone," Stiles points out, perfectly reasonably.

Derek smiles a smile equal parts fond and exasperated. "And there's the problem. Once someone's hadas many intimate moments with me as you've had, inspiring the same desperation isn't so easy." 'Easy' is reserved instead for nudging Stiles over onto his back again and resuming the exploration of his chest beneath his tunic, with Derek's knees planted by his hips.

Stiles squirms a little. "Me _knowing_ how good it's going to be doesn't help?"

Derek shrugs, tugging the fabric up to Stiles' shoulders. Idly, he begins to play with Stiles' nipples under his fingertips. "Wanting something is always going to be that much more consuming than having it. And _want_ that bad isn't good for a person. You can't hold someone in your thrall indefinitely, Stiles. Eventually, you've got to give them what they need or watch it destroy them."

"So... all that stuff I felt the _first_ time we did this?" Stiles has to ask, even though he feels like he's starting to get it now. "That doesn't count?"

"If you'd been under my thrall, I couldn't have put you under a geas," Derek explains, patiently, nudging Stiles up so he can get the tunic off over his shoulders at last. "You can't make deals with someone enthralled to you and expect them to hold afterwards."

If Stiles hadn't had a face full of fabric at that point, he might have left it there. As it is, though, he can't help muttering, "And I just gotta take your word for all this. Of course," as a parting shot, not even really knowing whether he wants to be heard or not.

Derek gives one last, faint sigh. "You don't want me to put you under my thrall, Stiles." He's working on Stiles' pants now, his focus low and distant. "You want to know you're not under it _now_. And if you were, trust me, it would never occur to you to ask."

Maybe the worst of it is, no matter how many knots he ties himself in, Stiles can't even pretend anymore that he doesn't know perfectly well Derek's right.

* * *

The fifth night finds the hunters camping on a strip of land between the two great lakes of Ashmore estate – they're not even on the Martin's land anymore. Stiles take the opportunity to ask lots of questions about just how 'running' does water have to be to act as a barrier to dark magical influences, and whether a few dozen fathoms of still water might work just as well. The Argents take the opportunity to test some inventive new ways to make the answer 'probably not, but frankly, your guess is as good as ours' come out sounding mysterious and threatening, with limited success. Everyone goes to bed tired and grumpy; even the poor sod left on watch has nodded off by moonrise.

This suits Stiles just fine, since it means no-one else is awake to see the smoke thicken into a pale mist when he tosses a handful of his favourite incense recipe into the midst of the fire. The belladonna berries were fresh this time; with any luck that ought to keep the influence in the air much longer than what little Stiles got out of his last batch. If all goes to plan, he should have a good few minutes to double check whether he has the right bag under his hand before his perception becomes suspect.

He lies there a while after, doing his best to breathe through an only-slightly-disgusting handkerchief, wondering idly how much time has passed, and how much longer he might have to wait; whether the hanky is doing its job or whether he's already got as much gas in his lungs as everyone else, and how he'd be expected to tell either way when the primary effect is to dull your mind just enough to keep you seeing whatever you would have expected to see regardless – and, all considered, whether this leaves him with any hope whatsoever of judging how much time might have passed in the first place. (By the standards of Stiles' thought processes under pressure, this is more or less what passes for 'idle'.)

Incense or no incense, there's no mistaking the moment when Derek hits the ground in the middle of the camp with a savage roar. Everything dissolves into chaos; Stiles gets a lightning glimpse of Derek holding one of the hunters off the ground by the throat and barely bites his tongue over the impulse to yell a warning not to take this too far before Chris steps into Stiles' line of sight and clubs Derek across the back with... maybe a log, Stiles can't make it out. He doesn't get to make out much of anything else from that point onwards either; Chris is still in the way and Stiles is busy doing the awkward dance of someone half-tangled in his own blanket and trying very hard to avoid getting stepped on in the fuss. This is a state of affairs which persists until the whole rumpus has moved off into the trees further away.

Stiles thinks about what an innocent bystander would be doing in a situation like this, and hides himself under a bush until the hunters come back.

"Did you get him?" asks Stiles' bush. "Is he gone? That was him, right – the incubus?"

In the light of the remnants of the fire, Chris and Kate look less than celebratory. "It went down over the lake," says Chris.

"Not much hope of finding the body in that much water," says Kate. "It went in a long way from shore."

"Can they swim?" says Stiles.

"With that many arrows sticking out of them?" says Kate. "Not likely."

"So he's dead, right?" says Stiles.

The Argents exchange a glance.

"One way to make sure," says Chris. "Get out the dagger. If it still works..."

"...our demon's still alive," finishes Kate, thoughtfully. "Clever. Stiles?"

"Right now?" says Stiles. Under the glares of both Argents, this gets swiftly revised to, "Oo-kay, can someone hand me the bag? Where'd it go?"

They find the bag lying in the fire, apparently kicked there at some point during the scuffle, much of its contents busily demonstrating enthusiastic flammability. The dagger, which had been carefully wrapped to preserve its aging bloody coating, is covered in a layer of ash.

"Yeah, I don't think that's going to work so well anymore," says Stiles, using his very best game face. "What do we do now?"

Chris looks a little bit like he just swallowed a chicken bone, but out loud he says, "We all heard it hit the water."

A murmur of assent goes around the other hunters. "It hit, then silence. Nothing came back to up," agrees Kate.

"Then until we're given reason to believe otherwise," says Chris, "we have to assume it's dead. You can't expect to come home from every hunt with a trophy."

"Then we're going home?" says Stiles, who really has no reason to hide his enthusiasm for the idea. He's done enough pretending already just keeping a lid on how scared this has him (though the real risk was never whether the hunters might notice, it's that they'll find out the real reason _why_ ).

"At first light tomorrow," says Chris, to the gathering at large. He turns to face Stiles directly. "I know it must be disappointing for the hunt to end like this after we've come so far, but without your help tracking it, we might never have pushed it into risking the frontal assault it made tonight. You've done well, Stiles. You should be proud of that."

Stiles makes a valiant attempt at smiling. "Oh, you know. All part of the job."

"Spoken like a true hunter," says Kate, smiling in one of those lovely ways that mostly involves showing all her teeth.

"Get some sleep," suggests Chris, "there's still a few hours left before dawn."

Stiles soon discovers that particular instruction is much easier heard than followed.

Up until now, he'd looked forward to having it all over with; now he's realising that the worst part is just starting: the long journey home _not knowing_.

It's not like he can expect Derek to just step out of the forest and grin at him like he used to back home; not with this many hunters watching his every move.

* * *

On the first night of their weary trek home, Stiles wakes in the dark of the night to the multiple-sense alarm-bell of someone leaning over him, covering his mouth so he can't scream.

He does what any sensible person would do, and panics.

Then he realises it's _Derek_ who's holding him down, and slumps through a multi-stage cascade of bone-deep relief. Derek, being Derek, fails to look remotely contrite about scaring the life out of him.

A moment later, Stiles remembers where he is – as in, in the middle of a circle of hunters with _Kate_ on watch – and panics all over again, where panicking consists primarily of Stiles waving his hands frantically in attempt to communicate _what the hell are you doing! Are you crazy? Get out of here before someone sees you!_

Unmoved by all the resulting flailing, Derek cups Stiles' cheek with his other hand and rests their foreheads together for a long moment. Then he's gone, suddenly as he appeared.

An inconvenient spike of arousal shivers through Stiles' body, but luckily fades again in time to let him make the most of the remaining hours he has before the hunters wake him up again for another hard day's ride.

* * *

They make much better time on the way home, arriving back at the tower just on sundown on the third day. Lydia does a convincing job of devoting her attention to the hunters' account of events when they all meet in the great hall, lulling Stiles into a perfectly false sense of security right up until the tale is told and the hunters distracted, and she catches his eye and gives Stiles a look that could wilt a pine tree. He makes his best attempt at giving her an easy smile that communicates, _all sorted, nothing to worry about_ smile in return, but between Lydia's expression, his own lingering doubts and days of exhaustion, he's not about to recreate that one in front of the mirror later.

Allison spends the evening looking at him with open concern and something very like understanding; she probably thinks they have an experience to share, and will end up trading horror stories about their first hunt any day now. Even _Jackson's_ giving Stiles this weird look, like he'd have something to say if there were a few less people watching – in between sneaking unhappy looks at Kate, that is. Stiles wants nothing more than the freedom to collapse onto his bed the moment he's dismissed, but he's not going to get it, because he's waited eight days to debrief Scott on the _other_ half of his brilliant plan, and like hell he's putting that off any longer.

Stiles gets himself dismissed before Scott that night, and spends an hour jittering on his bed and going back over every page of his bestiary for the umpteenth time. Finally, Scott comes in.

"So don't keep in suspense here, how'd it go?" Stiles demands the moment he's through the door. "And if you launch into telling me all about your uninterrupted week with Allison, I swear I will skin you alive!" Several different expressions flitter over Scott's face. "You're talking about that thing you asked me to do before you left? About that woman the hunters think-"

"-was killed by the incubus, yes! You did find the house, right?"

"That part was easy," says Scott, coming over to join him. "But what was inside was... weird." He wrinkles up his nose with the memory.

"I'm gonna need a little more than 'weird'."

"It smelled kinda like someone killed werewolf in there, or something," admits Scott.

"She was a _werewolf_?" How on earth could the hunters have missed something like that?

"I don't think so," says Scott, "There was a human smell in there too, all over all her things."

"Then maybe – maybe she was bitten," says Stiles, thinking aloud now, "and instead of turning, the bite killed her. That could explain the werewolf-smell." Though not how the hunters could've made such an obvious mistake over something they dealt with on a regular basis.

Scott shakes his head. "It wasn't her, Stiles. There was dead-human smell in there too, but the dead werewolf smell was... stronger," Scott wrinkles his face up even further at the memory. "Like it had been dead for a while."

"Well, what about the hunters?" Stiles suggests. "They deal with dead werewolves all the time. Could they have, like, tramped the smell in with them?"

"They never come home smelling like _that_ ," says Scott, with feeling. "Besides, I asked Allison, and she said they didn't even _see_ any werewolves on that trip. She had another idea though - she thinks she's heard of some rituals people used to do that use body parts from a werewolf. Like, some people used to think you could become a werewolf that way."

Stiles' stomach drops. "You think that woman was a _witch_?"

"Maybe," says Scott, but he doesn't look all that sure. If nothing else, you'd think the hunters would be on the lookout for telltale signs like, say, a huge black cauldron filled with newt eyes and werewolf organs sitting in the next room.

"So, suppose she was doing some freaky dead werewolf ritual, and something went wrong, and that'swhat killed her," Stiles says, working through it, "What happened to the dead werewolf?"

Scott considers this. "What if she wasn't working alone?" he suggests. "If someone else was involved, they could've covered it up before the rest of the village found her."

"Or maybe we're on completely the wrong track, and whatever monster really killed her killed a werewolf first and didn't bother to brush its teeth," says Stiles, frustrated. He's spent so long waiting to hear back from Scott that it'd been too easy to forget it had always been too much to hope that solving this would be that easy. 'Smells of dead werewolf' is the kind of clue that could mean _anything_ when that's all you've got. You could probably cover up a lot of other nasty smells by dragging a werewolf corpse over the scene, to throw out another example, but who'd _do_ that unless they already knewa werewolf would be coming past to sniff the place out? And if you wanted to hide something from a werewolf, why use a scent that would get any werewolf curious?

"Whatever it was, I think you were right," Scott offers. "Nothing about this makes sense for an incubus."

"The one that attacked Lydia," says Stiles, just to be sure, "it didn't smell..."

"...anything like the same," Scott agrees.

That doesn't leave them any closer to identifying who or what really killed that woman, but it's a safe bet the culprit's still out there, and the people who _should_ be out looking for it have _no idea_.

No matter what line the hunters have been trying to sell him lately, Stiles is very clear on how very much dealing with this stuff is _not_ his job. Unfortunately, covering for Scott and Derek apparently _is_ his job nowadays, and they can't take this to the professionals without giving Scott away. Meanwhile, as long as that thing's out there, it's only a matter of time before it kills again and sends the hunters into a whole new chapter of their incubus-hunting frenzy. He's got nothing that points to Derek – and Stiles is glad to have that, seriously – but he hasn't got much of anything else either, and his avenues for extra information are wearing pretty thin. He's already gone to an incubus, a hunter and a werewolf, and through every book he's got – what's left?

"You look like you maybe have an idea," says Scott, a moment later, and technically he's not wrong.

"Yeah, I might," says Stiles, feeling suddenly exhausted, "But I'm gonna sleep on it for now. You can tell me just how crazy it is in the morning."

**Notes for the Chapter:**

> The first part of [Other Things That Happened to Lydia Martin](http://archiveofourown.org/works/3638256/chapters/8037156) fits in at about the same time frame as this chapter, also featuring a glimpse at some of what Derek's been up to between scenes.


	7. Chapter 7

To Stiles' mild dismay, Scott makes no real attempt to dissuade him from his idea in the morning. If anything, he seems to think it's a pretty good plan.

"It's gotta be worth a try," he tells Stiles, after listening to the whole thing over breakfast, "and the hunters are never gonna do it, so that leaves us, right?"

Stiles nods absently along. "I mean, it's a risk, obviously – there's no guarantee they're even gonna talk to us, but if they're gonna talk to anyone, it's gotta be you, right? Of course, we're not gonna get this done without drawing attention to you, and I don't even want to _think_ about how many ways this could go south for us – especially if they take this as a challenge, but the way I figure it, you're gonna have to announce yourself sooner or later, and we could do so much worse than doing it on our own terms..."

"Stiles," says Scott, looking confused and slightly cornered in the familiar manner of people tasked with finding space for both themselves and Stiles' wild gesticulations in the narrower tower corridors. "I already said I think it's a good idea. Who are you trying to convince?"

"Me, mostly," Stiles admits. "What are we, _insane_? It's not bad enough that there's something out there sucking the life out of people, we've gotta go wander out into the wilderness and invite more trouble?"

"I can do this alone if you don't-" Scott begins to offer.

"Not with me following you out there, you won't," says Stiles, slapping him on the back.

Scott looks faintly like he's feels he's missed something and is trying to figure out what. "We've still got to get permission to go," he points out.

"Oh, we'll get it. It's Sunday, Lydia's in a good mood, and you sure didn't go visit your mum last week."

Scott's confusion deepens. "You weren't here, how did you know I...?"

"Scott," says Stiles, stopping at the door, "do me the favour of thinking about what you _were_ doing this time last week, then you get back to me on that."

Scott's 'thinking about Allison' face is at once endearing, a little sickening, and very distinct. "Oh."

"Yeah, oh," says Stiles, pushing through the door to their room. "So, I'll – Jackson?"

Standing in the middle of the servants' quarters, Jackson looks awkwardly out of place in a way even Derek-the-demon hasn't in a long time. Now that Stiles thinks of it, hadn't Jackson been trying to get his attention during breakfast once or twice? With everything else on his mind, he'd hardly noticed. "You want something?"

"I need your advice," says Jackson, looking nervous and furtive in a way that can only mean he's got himself into a special kind of trouble.

"You need _my_ advice?" This is officially an event without precedent. Stiles looks at Scott, but his friend is clearly just as confused as to what on earth is going on here.

"Well I'd rather have Deaton's, but since he's not here, you're it," snaps Jackson, sounding a little more like the Jackson Stiles is used to.

Oh, _that_ kind of advice. "Okay. Hit me."

Jackson's eyes flitter to Scott and back. "I'd rather discuss this in private."

"Oh, this is going to be good," Stiles breathes. "Hey Scott, how about you go clear our break time with Lydia, meet me back down here when you're done?"

"Sure," says Scott, though he gives Jackson a funny look before leaving.

Stiles pushes the door closed behind him and makes for his bed so he can fish around underneath it while he and Jackson talk about whatever it is the guy wants to talk about. Considering how nervous Jackson looks right now, either he's here to admit to some embarrassing personal complaint or he's worried he's got Lydia pregnant. Stiles really hopes it's the former; he does not want to be the one to deliver the advanced course of the-birds-and-the-bees with Jackson. If the honourable Mr Whitmore launches into a story about something that happened to 'a friend of his', Stiles is going to laugh in his face.

"So?" he prompts.

"How much do you know about love spells?" asks Jackson, without preamble.

Stiles whacks his arm against the frame of the bed. "You want me to do a _love spell?_ "

"What?! No!" Jackson's shock, at least, is wholly genuine. "I want to know how someone can _tell_ if they're under a love spell."

Stiles comes up from under the bed with the bag he was looking for in hand, rubs his arm and sits himself down on the mattress so he can deal with Jackson's new insanity with all the dismissiveness it deserves. "You think Lydia has you under a love spell?"

"Why do you think I mean Lydia?" Jackson hedges.

"Is there someone else you're messing around with? 'Cause even by your standards, Jackson, that's low." The face Jackson pulls is absolutely priceless. Poor bastard must have really thought he and Lydia were being subtle. " _Yes_ , I know about you and Lydia. For future reference: doors are made to close – pays to learn how to do that when you're having a secret affair. I'm telling you this for everyone else's sake if not your own."

Jackson sighs through his nose. "Okay. Fine. It's Lydia. How would I know?"

Stiles spreads his hands. "Well, you wake up one morning, suddenly desperate to woo someone you _haven't_ lusted after since the day you hit puberty, that would be your first clue."

"What, just because _you've_ been crazy for her that long, now everyone is?" Jackson sneers, and Stiles is officially never going to understand what Lydia sees in the guy. 

"Jackson, please. You and Lydia are not a secret." Stiles lays it all out for him using small words. "Your years of hopeless pining are _not_ a secret. Your stupid fling with Kate last year is not a secret, and – hate to break it to you – but neither is how hard you failed to make Lydia jealous with any of that. None of this is news."

If Lydia's name had thrown Jackson off his game, Kate's hits him like a slap to the face. "Kate? Why would you... what's not a secret about-" he stammers. Stiles officially gives up on getting any sense out of the guy today.

"Uh, that you slept with her last year, then went strutting around making sure everyone knew?" Stiles reminds him. "That she ditched you the moment you started taking it for granted, and you've loathed her ever since? If there's more here I don't know about this, please feel free to keep it that way."

"Is that what you thin..." Jackson takes a deep breath and collects himself. "It's different with Lydia."

"Great, I'm so happy for you. What's the problem?"

Stiles watches Jackson open his mouth and close it again, then glare helplessly off into the corner without coming up with a single word to express whatever torrid emotion he's experiencing. By Jackson's standards, it's almost cute.

"Aw, you getting all mushy over her now she's helping polish your hilt?" Stiles almost goes to slap Jackson on the back, but thinks better of it before he makes contact. He turns to movement into an elaborate gesture instead. "That's why you think she's got you under a spell? Hate to break it to you, Jackson, but that's no spell, that's just what they call loooove."

Jackson remains unconvinced and even less amused by this revelation. "Stiles, _everyone knows_ her mother was a witch. Did you never wonder if it might run in the family?"

Stiles' jaw drops. If this was rich before, it just hit indigestible. " _Seriously_? You do realise the witch thing was a load of raw baloney cooked up by Lord Martin's advisors when he needed an excuse to divorce her without looking like the bad guy, right?"

"Is that what you believe?" asks Jackson, whom Stiles has evidently been giving _way_ too much credit in the critical thinking department all these years. "Awful convenient how she up and vanished overnight before she got to trial."

"Try 'awful clever how she skipped the country before they could put her in thumbscrews," Stiles returns. This is going nowhere fast if he can't get them off this ridiculous tangent. "Look, even if you buy the idea Lydia's been practicing witchcraft in a tower full of hunters, _why_? Why would she cast a love spell on a guy who wanted her already?"

"Look, just – _humour me_ here, okay?" growls Jackson, holding himself back by inches. " _How would I know_?"

Stiles lets out a long and seriously heartfelt sigh. This conversation is starting to give him the weirdest sense of deja-vu, and it's not helping. "Well, the fact you're in here asking me is a pretty good sign. First symptom of a love spell is that the love comes blind and unconditional. We're talking raw infatuation – like dedicating songs to the colour of eyes you never even _noticed_ yesterday. That sound like what you're suffering from, Jackson?"

"Okay," Jackson concedes, "but what about something... not a love spell, just a spell that made me feel what I was already feeling, only more. Something to make me easier to _manipulate_."

"Sure, there are spells to do stuff like that," Stiles agrees. "I hear the main ingredient is a barrel of _good ale_. Jackson, seriously, what got you thinking this?"

Jackson's eyes flitter away. "Kate."

" _Kate_? Kate Argent? Kate-who-rid-you-of-all-shreds-of-virginity-Kate?" Well that explains a lot.

"It was something she said," admits Jackson, tersely.

This time, Stiles really does slap the guy on the shoulder. "Good news, Jackson! You made Kate Argent _jealous_."

"Jealous," Jackson echoes.

"Well, jealous in some weirdo Kate-way – which means it probably has more to do with getting huffy about how you've moved on than it does with her wanting you back – but I'm telling you, if _my_ ex came to me saying my new love magicked me into bed, I wouldn't be taking their word for it." Stiles watches Jackson's face as this new understanding sinks in. "C'mon, Jackson, she's a _hunter_. If she really thought you were under a love spell, don't you think she'd have Lydia in chains by now?"

"Obviously, if she had _proof_ ," Jackson snaps. "I never said I was taking her word for it. I'm here – asking _you_ – for advice because I don't have anyone else to ask!"

Stiles spreads his hands again. "Well, my advice to you is that you're not under a love spell, and Kate Argent just thinks it's cute to watch you panic. Good enough for you?"

Jackson produces what may be the world's smallest, most reluctant nod.

"Great. I'm glad we had this talk. We should do this more often; how's same time next year work for you?"

Jackson rolls his eyes. "Thanks for nothing, Stilinski," he says, and turns towards the door. Stiles is just about to enjoy the relief of knowing this is finally over when Jackson hesitates at the threshold to ask, "Me and Lydia... does that really not bother you?"

Stiles throws his hands in the air. "Okay, yes, it bothered me! Note the _past tense_ in that statement, because you can only cry yourself to sleep so many times before you gotta get over yourself and move on. None of my business."

Jackson looks a little unconvinced – and granted, Stiles is guilty of leaving out a few minor details relating to what a great help Derek's been in getting him over the spectre of Lydia Martin – but anything more he might have had to say on the subject is lost when Scott walks into him in the doorway.

Stiles latches onto the interruption like a lifeline. "Hey Scott! We clear to go?"

Scott manoeuvres himself around Jackson and nods. "She said it was fine."

Jackson looks back and forth between them. "Going somewhere?"

"Just off to aggravate the local werewolf population," Stiles tells him, hefting his bag. "You wanna come with?"

Jackson doesn't dignify that response, though he does finally leave the room, which is as much as Stiles was angling for.

"What was that all about?" Scott asks on the way out.

"Nothing big. Guy just wanted some romantic advice." On the edge of Stiles mind floats an unwelcome epiphany about his moment of deja-vu from before. If his conversation with Jackson felt familiar, that might just have something to do with how it was basically the same conversation he's been having with his neuroses almost nightly ever since the first time he started this thing with Derek, only with the phrase 'demonic thrall' replaced with 'love spell'. The important thing to remember is that Kate is _hardly at all_ involved in Stiles' version, and that Jackson never has to know.

"You give romantic advice now?" asks Scott, with all the incredulity that idea deserves, conveniently interrupting Stiles' little moment of clarity.

"I know, right?" What the hell, they've got work to do. He can wallow in his own hypocrisy later. Probably while sleepless at around 3AM tonight. "C'mon, let's move."

* * *

A couple odd miles from the tower, in a direction well diverged from that which anyone would expect him and Scott to take to reach Mrs McCall's home village, Stiles drags himself to the flattened top of a low, sparsely-forested hill. There's nothing greatly significant about the spot, but it's high enough to give them a decent chance of spotting anyone coming in advance, and it'll give them the space they need to put their plan into action. By the time Stiles makes it to the top Scott and the bag of mountain ash are already waiting for him, though Scott will have to wait a little longer yet while Stiles lays out a careful ring around the peak.

"Wanna test it out?" Stiles offers, hopping over the line to join Scott inside.

Scott gingerly extends a hand toward the edge of the circle. "Yeah, that's working."

"Okay," says Stiles, wiping his hands off on his pants. "Over to you, buddy."

Scott takes a long, deep breath.

The howl echoes down the slope and away into the distance. Even in broad daylight – even _knowing_ Scott is the least terrifying werewolf you could ever hope to meet – it's all too easy to imagine that every leaf in the forest has stopped to listen; that you can feel the deeper rumble of the underlying roar resonating through the earth at your feet. Stiles is pretty sure he feels every hair on his arms standing to attention.

"Nice work," he offers, weakly. Scott gives him an answering shrug-and-smile, and they both go back to studying the treeline for any hint of movement.

"Any idea how long we're gonna have to wait?" Stiles asks.

"Not really," says Scott. "I guess it depends how far away they are."

"You think you'll be able to, like, smell them coming?"

Scott scrunches up his nose. "Only if they come at us from upwind..."

"Which would make upwind the direction they're least likely to come at us from," Stiles decides, with a sense of dry inevitability. "What about your hearing? Can you hear anything?"

In the distance, something howls.

"Something like that?" offers Scott.

"Thaaaat really wasn't an echo, was it?" Talking when he's nervous is a habit Stiles has never managed to break. Answering howls join the first from another direction, the voices overlapping and uncountable. "Oh boy, the whole pack's turning out for this, isn't that nice."

"There might not be as many as it sounds like." Scott's obviously trying to be comforting, but the comment comes across as more of a tactical note. The howls are getting closer; every rustle in the bushes is starting to sound suspect to Stiles. Much more of this and he'll be seeing a wolf in every shadow down there.

Several sets of glowing eyes now peering out at them from those same shadows aren't so much helping with that either.

"What are they waiting for?" he hisses to Scott. Scott shushes him, off-handedly, and Stiles is about to protest when he realises one of the dark shapes has left the trees.

"You have a bold voice, pup; bolder still to raise it in our territory, when you come here reeking of humans and the hunt." The voice rings clear but low, pitched to carry. The approaching werewolf is female, probably somewhat older than Stiles or Scott, though her frame is scrawny and underfed. She's dressed in a well-worn tunic and an uneven leather skirt, the long hair of her beta-form braided into tresses that hang over her shoulders as she rises to her feet outside the circle; keeping her distance, eying the both of them with open distrust.

"We don't want any trouble, we only came to talk. I... you're not the alpha," says Scott, confused.

"Yet I'll wager I'm longer in the tooth than you." The werewolf gives them a feral grin, but before Stiles can quite make up his mind whether she just _made an actual joke_ or whether she was just threatening them, all semblance of humour is just as suddenly gone. "You're neither pack nor kin to me and mine, what grounds have you to demand my alpha answer your summons?"

Scott is visibly taken aback. "I didn't mean – I just thought he'd be the one to speak to us."

The werewolf begins to pace, circling their position, though she maintains her distance. "If you wish to join our pack, _omega_ , you've left it late. How many moons have you skulked in that tower, hiding at the hunters' feet?"

_They know_ , Stiles thinks desperately. _How long have they known he was there? Did_ Scott _realise?_ He turns to Scott, but Scott's attention is elsewhere.

"I've lived in that tower _all my life_ , and I'm not here to join your pack," Scott protests. "I never asked for this, it was forced on me."

The werewolf tilts her head. "Not by our pack."

"I know," says Scott. "I've no quarrel with your alpha. We honestly just want to talk."

"That's why we put down the mountain ash, see?" Stiles adds. "We stay on our side, you stay on your side, no-one has to get hurt."

"You hide behind witchcraft and trickery!" the werewolf spits.

"We were sorta aiming more for a gesture of good faith," Stiles offers. The werewolf's only reply is a loud snarl. "No? Okay, we'll know for next time."

"Why should I trust any word you say?" she demands. "You've had time enough to show where your loyalties lie. You bring a human as your second, call us from our woods and cower behind rowan ash! Your hunters have set less likely traps than this. They harry our young and desecrate our dead! Omegas left packless and desperate have done worse for the empty promise of their own lives."

"Whoa, no, you don't think we're..." The idea is preposterous Stiles doesn't even know how to object. What kind of idiot lies to a _werewolf_?

"Can't you listen to our heartbeats and tell?" says Scott, who, for once in his life, has got there faster than Stiles. Slowing his voice, he pronounces, "We don't mean you any harm. We're no closer friends to the hunters than you are."

"In fact, that's why we're here," Stiles puts in quickly, before Scott's remembers that one hunter he's quite the close friend of and his heartbeat gives them all away. "If you'd just hear us out, we think we could help each other on this."

The werewolf continues to growl softly, but she doesn't object in more detail than that – and, well, Stiles has never been one to waste an opportunity to talk.

"There's something else out here – something that's killed at least one human already, and it might be killing werewolves too," Stiles pronounces, speaking slow and clear. "The hunters think it's an incubus, but we think they're wrong. The first woman it killed – the first human woman, I mean – was found looking like she died in agony but without a mark on her body. It left behind this smell..." Stiles looks to Scott for a description.

"Like a dead werewolf," finishes Scott. "And not just dead. Like it had been left to decay."

"That's why we came to you," Stiles goes on. "If there's been something killing werewolves – if there's anything you can tell us at all, that could help us identify this thing before anyone else gets-"

The rest is drowned out under a furious snarl from the werewolf – one that picks up an echo from beyond the treeline, where the owners of rest of those glowing eyes have kept pace. "What kills our kind?" she snarls "You mock us with this charade!"

"It wasn't the hunters this time!" Scott protests. "They never-"

"Even in death, they no longer grant us peace!" The werewolf's voice has risen to a roar. "Tell your hunters if they owe us so little respect they will defile the graves of our fallen again, soon even the babes among them shall know our wrath!"

With that last ultimatum, she turns tail and vanishes back into the woods, the sounds of the pack in flight quickly fading away behind her.

Stiles sits down heavily. "That could have gone better."

Scott gives him a helpless look. "You heard that thing she said, right? About... 'graves of the fallen'?"

"And 'desecrating the dead', yeah," agrees Stiles. "Someone's been _digging up their dead_. Oh my _god_."

"They think it's the hunters," says Scott.

"Are we sure it _wasn't_?" says Stiles, because someone has to. He toes at the line of mountain ash. "You think it's safe to break this now?"

"Huh? Oh – sure," says Scott absently. "But it _can't_ have been the hunters. If they'd ever come home with that smell on them," he wrinkles his nose and grimaces in what must be a memory he'll not soon forget, "There's no way I could have missed it."

"So where's that leave us? Back at the witch theory?" Stiles breaks the circle and tugs Scott by the arm to get him moving; he doesn't much like the idea of hanging around here any longer than they have to, and they can talk and walk at the same time. "Did Allison ever find out how fresh that 'eye of werewolf' stuff has to be?"

"She couldn't find much about anything," says Scott, dejected.

So much for outside leads. "I guess we're just gonna have to go back to the house again, hope we can find something everyone else missed."

Scott pulls a face that suggests he's remembering that smell pretty vividly already, and not so much relishing the idea of spending another few hours poking around at the source.

"C'mon, Scott, it's been days; the smell's probably dissipated already. And if not, I'll need you there to let me know, because that means..." Stiles waves his hands so as to generally indicate the possible existence of remaining bits of dead werewolf that might still be lying around, which could turn into their best evidence yet that something non-incubus-related is going on.

Scott, unfortunately, seems to have interpreted this gesture correctly. "I swear I can almost still smell it _now_ , it was that..." He trails off, nostrils flaring, but before Stiles can get as far as asking what's up, Scott grabs him by the arm and hisses, "Stiles, _there's something coming!_ "

"Another werewolf?" Stiles fumbles for the mountain ash. Did one of the pack come back? Or is this a whole different pack? Scott's howl could've carried for miles; _anything_ might have decided to check it out.

"No, it's coming from upwind!" Scott insists, and Stiles has barely started to put together what that means before Scott continues, "Stiles, it's _that smell!_ "

Stiles gapes at him. Scott keeps his eyes fixed on the woods to the east – the trees go almost to the top of the slope on that side, and by the time _that thing_ comes lumbering out into the open, Stiles can smell it too.

When you're expected to wait on formal dinners attended by a party of hunters several times a week, you end up playing audience to more than your share of lurid tales about The True Forms of Alpha Werewolves We Have Faced: horrifying twisted monstrosities, half-human and half-wolf – ten feet tall in the light of the moon, with fangs like razors and claws like knives, with eyes that can stare down a grown man and freeze him to the spot like a scared rabbit.

This thing stands no taller than an 'average' werewolf and is no more wolf than the average beta, but its flesh is pale and drawn, its lips and gums so shrivelled that its teeth seem twice as long as they should be. The veins lining its skin run thick and black, pulsating visibly with every heartbeat – these come seconds apart, laboured as if every beat might be its last. Its eyes are solid white, glowing only weakly as the creature lumbers towards them; whatever colour they might have been in life leached utterly away. Every move it makes, all Stiles can think is that he's never seen anything that wears its body so _wrong_.

It might have been male once; how old, he wouldn't have liked to say.

Obviously Stiles isn't actually planning to stand there staring at the thing until it eats him, but 'what do we do if a _zombie werewolf_ comes out of the woods at us' wasn't exactly in today's list of pre-prepared scenarios. Scott takes charge, yells, "Stiles, _go!_ " and puts himself firmly between his friend and the monster.

"Go _where_?" Stiles protests, because like hell he's running off into the woods if there might be more of _those_ lying in wait for him. That said, he doesn't need Scott's permission to back up a few paces, putting a little space between himself and imminent toothy death while he concentrates on thinking his way out of this. There was some mountain ash left in the bottom of the bag but he'd dropped it before the werewolves showed up. He spots the bag lying well out of reach, closer to the zombie-wolf than it is to him. So much for any clever ideas about leaping for it.

Scott and the zombie-wolf are still locked in the circle-and-snarl phase of the standoff, following that time-honoured tradition of puffing themselves up to see if either party can be convinced to back down before blood is drawn. This would be worth more to Stiles if Scott had only had the decency to circle in the right damn direction, but no such luck – anti-clockwise it is, which means Stiles is having to scamper even further from the bag to keep Scott between himself and danger. No-one's going to back down here; Scott is hardly about to leave Stiles undefended, and the zombie-wolf responds to his snarl with a low growl-roar – the sound that escapes its lips is _tortured_ , there's no other word for it. Just for a second, Scott falters. The zombie-wolf leaps for him; Scott meets it somewhat less than halfway, and Stiles throws himself towards the mountain ash all at once.

Life-threatening panic does not a graceful Stiles create. He pitches almost right over his own feet in his rush, makes the mistake of looking up at a particularly vicious growl – Scott is holding the zombie-wolf's teeth away from his face by _inches –_ and really does lose his footing in the loose soil, crawling the last of the distance on his hands. He's shaking when he gets a hand them into the bag – there's precious little ash left, barely more than enough for a circle that'll enclose him standing up, if he doesn't lose most of it to the breeze in the process. He has less than half of the ugliest circle he's ever traced down before there's an ear-splitting _crunch_ from somewhere off in the trees. When Stiles looks, someone's feet are sticking out of the branches over twenty feet away from where Scott and the zombie-wolf were fighting a moment ago, only Scott is missing suddenly and those feet look _really familiar_.

The next thing Stiles realises is that the zombie-wolf looking right at him and coming his way.

It's bleeding sluggishly from a half dozen gashes Scott must have scored into its face and throat. They're not healing the way Scott's would, but they're not slowing it down either. By the time Stiles has got as far as realising he doesn't have nearly time enough to finish his circle before it gets to him, he's got maybe a second left. He throws what's left of the ash at the creature's face and bolts.

Somewhere behind him, Stiles hears the zombie-wolf howl in pain. Because he's not entirely stupid he _doesn't_ stop to look back over his shoulder, though because he's still Stiles, he does ( _without stopping_ ) find time to wonder exactly what it's like for a supernatural monster to take a handful of monster-repelling dust to the sinuses, and whether his improvised sand-in-the-eyes move had in fact been a moment of unrealised genius, and _that's_ when the hand closes around his ankle and literally pulls it out from under him.

The thoughts _this thing sucks life out of people_ and _I'm going to die_ flash through Stiles' mind in only slightly more time than the world takes to flash through his vision on the way down. Every instinct worth listening to is telling him to struggle for everything he's worth, but having just been slammed chest-first into the dirt, he's too stunned and winded for 'all he's worth' to amount to very much. Several precious seconds into the 'eventually', it registers that the grip on his ankle is gone, that there's nothing holding him and he's wasting his chance to flee before the monster's on him again. 'Fleeing', however, doesn't get him much further than a weak attempt to claw his way to safety with his fingernails in the dirt.

Stiles shoves himself over onto his back just in time to hear the zombie-wolf howl what could be the last howl its latest victim will ever hear. He throws his arms in front of his face in one last-ditch attempt to protect himself – from a blow that doesn't come.

The blow doesn't come because the zombie-wolf wasn't howling at him at all. It's howling at Scott, who's perched halfway up the creature's back. With a horrible, drawn out noise that will doubtless haunt his nights for years to come, Stiles watches Scott tear its head clean off its shoulders, inch by tortured inch. The zombie-wolf doesn't stop moving until the very end, and collapses to the ground, muscle by muscle, like a mountain of dry sand.

Scott comes away covered in dark blood and regains his feet with a stumble, but holds them – more or less – as he comes over to make sure his friend's okay. Stiles doesn't congratulate him on his first werewolfly victory, and Scott doesn't say, "You think we still have time to go see my mum?" It's a little while before either of them can think of anything worth saying at all.

* * *

Derek shows up that night well before Stiles has even considered thinking-about-wanting-him-there, in the deliberate sense – which is the sort of important distinction his life has been starting to develop these days. Fortunately, by the time he's alone to be visited, Stiles has already put a very productive few hours of collaborative research behind him, and isn't likely to complain too hard about being pulled out of his bestiary because Derek wants to chat.

"Someone's early," he calls, at the now-familiar sound of Derek's feet hitting the floor. "Warning you now: don't know if I'm gonna be up for anything fun tonight; I'm just about one big living bruise after this monster _tried to eat me_ earlier."

"I know," says Derek, in one of those deceptively quiet tones which probably means something terribly significant, only Stiles wastes his opportunity to figure out what because he's too busy catching up with what Derek's saying at all.

"Wait... you _know?_ How?" Stiles looks up to see what might have been concern vanish from Derek's features under the more familiar _you're-smarter-than-this_ sardonic glare. Understanding dawns, embarrassingly slowly.

"You _felt_ that?" In retrospect, he feels a little dumb to have gone through his entire near-death-experience without remembering that he has a reasonably intimidating demon at his mental beck and call – which is a pretty breathtaking thought, now the non-sexual implications are coming to him. He's pretty sure he wouldn't have called Derek in anyway, since for one, it had all been over far too fast – and for another, he doesn't even want to think about how he'd have explained it to Scott in the aftermath – but if getting himself into life-threatening danger becomes a habit, that is notan option he's going to overlook twice. "Oh my god, how much did you _get_?"

"The part where you _didn't want to die_ came through fairly clearly," says Derek, tersely – and Stiles can sympathise, really. Getting an unexpected blast of imminent _oh my god gonna die_ from a source you usually associate with _desire_ and _sex_ wouldn't be fun for anyone.

"Well damn, sorry about that – I'll try and warn you in advance next time I go wandering into mortal danger."

"That's not..." Derek visibly has to stop and gather himself. He takes a breath. "Stiles, what happened out there? _All_ I know is you were scared."

He should probably remember to thank Derek later for giving him that opening. "Hey, here's a good riddle: what smells like a dead werewolf and sucks the life out of innocent villagers for fun?" Since odds are Derek's not going to play along, Stiles skips straight to the less-cryptic version. "Does the word _volkodlak_ mean anything to you?"

Derek's forehead creases slightly. "It's another word for werewolf, isn't it? Or... vampire?"

"Close, but it's more like _both_. The word comes from a legend from way out east somewhere, where people believe that when a werewolf dies, it comes back to life as a vampire: a volkodlak. Which we all know doesn't happen, because if it _did_ the hunters would have found out about it years ago – it's not like you see them going through the stake-and-burn routine on every dead wolf they get. As far as anyone knows, the volkodlak is just one of those weird old superstitions that real scholars don't even pay attention to anymore – pure fantasy." Stiles takes a much-needed breath. "Until one tried to kill me and Scott today."

"You were attacked by a _vampire-werewolf_?" 'Only you, Stiles', Derek's expression seems to say.

"If you've got a better explanation, I'm all ears." They only have a name for it at all thanks to Allison, who listened through their sordid tale and remembered something from the dusty pages of the oldest hunter lore – the kind of useless detail the youngest recruits read about once in their historical textbooks and never hear about again. Stiles old found the matching entry for _volkodlak_ hidden in an appendix to his own bestiary later. "This wasn't just any werewolf, it looked and it damn well _smelled_ like a dead thing – same smell Scott picked up in that dead woman's house. He had to rip its head just about clean off its shoulders before it stopped moving. And the local pack just got through telling us all about how they think someone's been _digging up their graves_."

"When the truth is, what, the dead have been digging themselves out?" offers Derek, frowning.

"Maybe. I don't know, figuring out exactly how a monster that only exists as a mythical footnote is supposed to go about rising from the grave is not actually something I've solved yet!" Stiles fixes Derek with a frustrated glare, which Derek, being Derek, opts to ignore.

"Was it just the one?" he asks.

Stiles lets out a sigh. "I don't know. The werewolf we talked to wasn't that clear on whether the grave-robbing was one or many. But until we know what inspired _one_ werewolf come back from the dead and take up sucking life for sustenance..."

"...we don't know for sure there won't be more." Derek finishes for him.

"Have I mentioned how much this isn't supposed to even be my problem?" Stiles complains. "This is what hunters are supposed to be _for!_ But our hunters are too busy trying to hunt down my best friend or catch my..." For once, words have failed Stiles, and he settles for waving a hand generally in Derek's direction, "whatever you are, and I can't tell them I met a vampire-werewolf without having to admit I only made it out alive because Scott's not human, and I only knew it _wasn't_ an incubus because _one told me!_ "

Derek raises an eyebrow at him, unmoved. "Are you asking for life to be _fair_ ,Stiles?"

A weak laugh escapes Stiles' lips. " _Unfair_ is having to cover for your best friend after he gets _bitten by a werewolf!_ Covering for an incubus who got himself framed for a murder is way more than I signed up for. You realise stuff like this didn't happen here up to a few months ago? Then suddenly we've got not one but _two_ incubi on our doorstep, plus a vampire-werewolf invasion of unknown size. A guy could get _suspicious_ , that's all I'm saying."

Derek gives him a long, dark look. "What exactly do you want from me, Stiles?"

The answer to that is too huge to contemplate. Stiles gives in and comes back to what he knows. "You brought me a book once on mountain ash barriers. If your source-I-don't-want-to-know-about can get me anything on obscure werewolf-legends..."

Derek nods, though he seems uneasy. "I'll see what I can find."

"Great, you do that." Stiles rubs his eyes, feeling suddenly very tired. When Derek doesn't make any sign of leaving, he adds, "Was there something else you wanted?"

"There was, actually." Derek takes a step towards the bed. Stiles' body makes the least of all token attempts at summoning the usual responsive lust, then gives up on the spot. The honeymoon period of his obsession with Derek has never before felt so over.

"Derek, I do not even have the words to express how not in the mood-" is as far as Stiles gets before the envelope hits the bed.

Stiles looks at the envelope and back up at Derek again. "What's this?" he asks, picking it up.

Derek folds his arms and waits while Stiles turns the envelope over and finds his name written on the other side in familiar, uneven letters; draws a sharp breath and scrambles to open it so he can know for sure.

It's from his dad. The date at the top of the parchment is only weeks ago.

"What the... I... how on _earth_ did you _get_ this?" It may be a logistic impossibility for Stiles to read the letter _and_ shake Derek down for some answers at the same time, but he's damn well going to try. Even on a cursory scan, there's no question that it's genuine. His dad talks through the same trivialities Stiles is used to: recent skirmishes with the enemy are referenced only in passing – Stiles isn't dumb, he knows his dad will be downplaying the danger – but mostly the letter echoes what he'd already gathered from standing around the great hall at mealtimes: the standoff at their defences is holding, so his father writes about the cold and rationing; the rumour mill among the other soldiers, his hopes that his son is keeping well in his absence...

Stiles isn't going to get one more paragraphof research done tonight; he'll be reading this letter over and over until he falls asleep on the page.

"Your _steward_ must have misplaced it," says Derek, spitting the word 'steward' with a distaste that warms the very cockles of Stiles' vindictive little heart. "It came with the rest of the mail, then turned up stuffed in the back of his bookcase wedged behind two outdated volumes of property tax records. An accident, I'm sure."

Derek's not wrong. Harris is exactly petty enough to 'lose' Marshal Stilinski's letter – it's just one more switch with which to punish the Stilinski men for having the gall to notice the seedier side of the Martins' steward's reputation, or those one or two little discrepancies between what taxes the peasants paid and what got reported. Nothing had ever even come of it, to Stiles' dismay – not beyond making Harris just nervous enough to be more careful – but the insult had never been forgotten. Stiles would be overcome by righteous fury himself right now if he wasn't already overwhelmed twice over that Derek got this to him at all. "You – why... no, no I don't even _want_ to know why you'd be snooping around Harris' office. I just... how did you know?"

Derek shrugs, like conveniently finding letters stuffed in the back of other people's offices is something people do everyday. "You wanted it, didn't you?"

It's true; Stiles wanted that letter to exist more than he's wanted any concrete thing in months. If Derek's so in tune with Stiles' desires that he'd picked up on that, that's maybe something Stiles should be worried about, but from here it's hard to see the downside.

From nowhere, it hits Stiles that he thinks maybe his dad would have _liked_ Derek, in some other universe where Stiles could ever picture introducing them. Hunting, magic – _everything_ Derek represents is as far beyond his father's experience as anything on this earth, but he's always been old-fashioned enough to believe in paying his debts, no matter who the debtor might be. If keeping the existence of an incubus secret is the price Stiles has to pay for his and every other life in the tower Derek must have saved when he showed up that night... his Dad might just understand.

It's a bigger thought than Stiles has anything like the faculties left to process after everything else tonight.

"You need some time alone?" Derek offers, from what feels like a thousand years ago.

Stiles finds himself blinking rapidly to clear his eyes. "I... yeah." _Thank you_ dies on his lips, because it's not even close to adequate. They don't _do_ this – this honest emotional crap, and he's got the feeling there's a good reason for that even if he can't remember it just now.

Derek's all the way to the window before Stiles manages to add anything else at all, but what comes out is only, "I'll see you tomorrow?"

It's hard to make out that far from the candlelight, with his eyes all damn misted up, but he thinks he sees Derek smile at him.

"You will," says Derek, and then he's gone.


	8. Chapter 8

Willing and eager as Stiles may be to bury himself in research first thing in the morning, the real world has other ideas.

For that matter, so does Derek – who has been very patient through the eleven days Stiles has taken to get the hunters off their trail and put the last of his doubts (and one reanimated werewolf) to rest. But as they say, man cannot live by bread alone or... well, something like that but applicable to demons who live on sex, and by the evening of day twelve Derek is ready to pounce on Stiles at the very first opportune moment. Stiles remains a little hazy on how the whole _sensation_ thing works for incubi; he has the general idea it's not quite the same as what it's like being a teenage boy who's gone without for eleven days straight, but distinctions like that pale somewhat while Derek is trying to take off your pants. Figuring he owes Derek at least that much, Stiles magnanimously opts to postpone the Very Important Things he needs to tell Derek tonight until _after_.

(For at least a solid twenty minutes that follow, Stiles finds no cause to regret this decision whatsoever.)

"So, that big trip we've been prepping for is tomorrow," he tells Derek later, in the gap between round one and – given that Derek is about to hear that tomorrow and the day after are off as well – what's bound to be at least another two rounds before any sleep happens tonight. "You know; get the household into town in time for the spring fair and that."

Beside him on the bed Derek stretches and opens his eyes. "You've mentioned it. That's tomorrow?"

"Yeah, kinda snuck up on me." The whole truth is that in the excitement of the past two weeks, Stiles had forgotten the impending move altogether. He'd maintained this pleasant state of forgetfulness up until Scott prodded him awake that morning with the news that they were supposed to be on the road in under twenty-four hours, that they were both supposed to have been up most of an hour ago, and that Harris was on the warpath looking for him. Stiles finds it terminally unfair that life should expect him to remember minor obligations like that after the month he's had. He thinks he's doing pretty well to be out of bed at all, considering. Harris and Lydia, unfortunately, hadn't much seem to agree.

But mundanely annoying as the day might have been, Derek doesn't need to know all that. What he needs to know is where to look for Stiles if he wants to pounce on him while he's alone in the next few _months_ , which is how long it'll be before Stiles can expect to lay eyes on the tower again. "If you wanna come find me while I'm there, it's not hard to find," he tells Derek, "you just follow the road south until you get to-"

"The castle on Beacon Fell – Beacon Fell the _landform_ , not the town, which is also on Beacon Fell, mostly. Not hard to find, being as it's the only town on high ground _or_ next to a castle of that size within at least a hundred miles of here," finishes Derek, with no small impatience. "Yes, Stiles, I do know where that is."

The effect is just a little like that time he heard Jackson talk authoritatively on the subject of taxes and tenant rights for several minutes out of the blue. "Have I mentioned lately how it creeps me out when you know normal people stuff like that? How much geography do you even pick up lurking outside people's homes at night? "

Derek gives him the sort of long look that statement probably deserved. "Do you actually want an answer, or is that just going to ruin it for you?"

Stiles picks option three and drops the subject. "Okay, so you can find the place. Don't bother looking for me there before Friday though – those of us who can't fly have three fun-filled days on the road to look forward to before we get there. I'd give you directions to my room, but I'm pretty sure you're going to find that just fine without help, so..." That should about cover everything, right? Stiles is unaware of any formal etiquette for giving one's demon lover a forwarding address, but the surreality of the exercise is throwing him a little. People normally move to get _away_ from things like Derek.

He can't help but feel there's something going on here he's missing, and in trying to pin it down, Stiles makes the mistake of realising that Derek has not yet said, in so many words, that he plans to play along and follow Stiles to his new haunts at all. Stiles also realises that this is perhaps the worst possible moment he could have chosen to have this particular revelation. He starts to babble. "I mean, that's – you know, if you're coming. If that's not too far out of your way, or. Um."

Derek deals with Stiles' momentary lapse into panic by laughing at him. Stiles would be offended, but he's too busy being relieved.

"Don't strain yourself," says Derek, grinning a toothy grin. "You aren't getting rid of me that easily. You'll see me down there, I promise."

If there's any important subtext to that statement, it lies buried under too many layers of relief and embarrassment to make any impression on Stiles. "Thanks, I think."

Stiles goes on to get two more orgasms, five hours sleep and no more than the slightest of impressions that Derek is still laughing at him out of the rest of the night, and is content to call it all a win.

* * *

So it is that with a lousy three nights' rest between him and the hunt, Stiles is on the road again. No horse for him this time; that honour is reserved for nobles and hunters. Mere servants get to ride packed into an overstuffed wagon, wedged between Rebecca and a chest of Lydia's best dresses, feeling every stone and pothole rattle up his spine. That's excepting uphill stretches and patches of rougher road, when all extra weight is expected to carry itself. In his experience, the road between the tower and the town manages to be is mostly uphill in both directions.

Stiles has been attached to the Martin family long enough to be used to seeing the household uprooted a couple of times each year, so that their oversight might be divided more evenly around each corner of the estate. If he's honest though, it's more than a little weird to experience something so routine after all the excitement of the past few months. The feeling of something subtly off-kilter is only magnified by the presence of an entourage so diminished over the last two winters that it numbers not even a third of what would usually accompany their lady on the road, with permanent castle staff waiting to receive them at Beacon Fell reduced all the way down to one guardsman and an elderly pigeon-keeper, and the tower guard left behind totalling only two unfortunate junior hunters (whom Stiles can only hope don't hate the sight of each other already). Or the fact that no matter how carefully they may have packed the carts to disguise it, he can never quite make himself forget that, under the piles of candles and linen, _all_ of the Martin family's remaining jewels and valuables are travelling with them (most of which were never properly unpacked at all). There's nowhere else safe to leave them anymore.

At least the company's better than it was on the hunt – even if there's not much to do a lot of the time but watch Scott and Allison pretend _not_ to make eyes at each other every time the road widens to let her horse to fall into step beside the carts, or listen to Jackson and Lydia bicker and flirt in euphemisms that get increasingly less subtle as the day wears on, and wonder privately how there could be _anyone_ left in the tower anymore who doesn't know exactly what's going on right under their noses.

"Don't look at me," says Rebecca, who has no respect for privacy. "You think _they're_ bad at keeping a straight face, you should see _me_ doing all their laundry."

But despite all Stiles' most paranoid impulses, the journey continues uneventfully and they make good time. Before the afternoon has grown old on the third day out, the countryside scenery has given way to the familiar site of the field outside the castle walls – already dotted with merchant caravans and more people than Stiles has seen in months. By this time tomorrow, what was an open expanse of green will be a maze of stalls and shade cloths, a cacophony of musicians and hawkers. He can't help it: the sight grabs something young and childish in the base of Stiles' chest and makes it dance with glee.

He arrives in the castle courtyard charged with a manic energy that carries him all the way through his part in helping unload all the carts, and even most of the way through the slog of being expected to transport his lady's luggage around the castle, air out several rooms thick with months of dust and help prepare for the evening meal. Having made it that far, however, his remaining energy leaves him so suddenly that he all but crashes on the spot.

Scott, powered as he is by inhuman werewolf endurance, joins Stiles in their quarters a little later, smelling of horses and happiness as he falls into the adjacent bed. Stiles has very nearly summoned the energy to lift his head and ask him to move downwind (or at least to a bed further away) when he hears the first broken-off snore from Scott's direction, and gives in. If the pre-fair excitement alone doesn't keep him up tonight, a little horsey smell has no chance.

* * *

Of course, when morning comes there are still roughly a hundred things to be done to keep Stiles from setting a foot outside the castle in a hurry, nominal hoy day or not. Last night didn't more than take the edge off the backlog of chores, and the days of seeing his father step in and send his son off to play are long behind him. If he had any impulse to complain about his lot, Lydia and Harris were hardly off their mounts before they were demanding detailed accounts from the toll collectors manning the entrances to the green, and are now only beginning to deal with all those 'matters of urgent business' which have arisen in town in their absence, and which just as urgently require someone to find _that thing_ which has been inevitably packed in completely the wrong box and could be just about anywhere. It's well after noon before Lydia finally takes pity on him, and sends him on an 'errand' to see what price the merchants are asking for a bolt of green silk this year, and no particular instruction to hurry back. Stiles is a blur in the distance before she can think of changing her mind.

The Spring Fair is inarguably a big deal, but it's the kind of big deal that's happened every year for as long as Stiles can remember. When you aren't in the habit of owning enough coin to afford more than the simplest of the luxuries on display, the excitement of seeing what's for sale wears off far more quickly, and there's not much here to see he hasn't seen before a dozen times. _Less_ , actually, this year – the Martins aren't the only ones feeling the leanness of the times, and the lines of stalls are a whole row shorter than there would've been a couple of years ago. For all the glamour of the occasion, Stiles knows perfectly well that most of the people out there are hardly richer than him, and are here to buy and sell livestock or looking for work. Before he even sets foot on the field he knows there's going to be a fiddler at each end with a hat out for his trouble, and somewhere in the middle there'll be a man who can balance on a rope and make handkerchiefs disappear, and probably a fire-eater or something keeping him company.

But when you haven't even seen a real fiddle in half a year, the Spring Fair sounds like just about the best thing this side of Christmas.

Still, even as he's taking his time among the stalls, there's a part of Stiles – one he's not all that proud of but he may as well admit to now and get it over with – that would rather be spending the day with Derek. With Derek back in his room, to be specific, because privacy aside, picturing Derek out here in the open in a field full of people is... is actually not that hard, now Stiles has the idea of it. In his head, Derek is making that face that he makes when he's trying to remember why he puts up with Stiles at all, when all he gets for it involves being pestered with questions, called in to test magic circles, and dragged to pointless human social events where _no-one_ has sex before sun down. For good measure, Stiles also pictures everyone else around Derek giving him a wide berth and shooting nervous glances at each other like they're trying to decide what he's got to do with the festival. Yup, way too easy.

So easy that when he spots Derek in the crowd a moment later, it takes him nearly ten seconds to get around to the double take.

It's not Derek, of course, it's just some guy over near the vendors who looks a bit like him – or like Derek would look if he were human. If Stiles could get a bit closer for a better look, it'd probably turn out half the resemblance is all in his head and whoever-that-is has a crooked nose or no eyebrows, and doesn't really look all that much like Derek at all. But getting closer would be a whole lot easier if there weren't a sea of heads between them, or if what's-his-face wasn't walking away from Stiles like he's in a hurry to be somewhere else, or if the guy would only have the decency to turn around for a sec so Stiles can get a proper look at his face already.

The man Stiles is chasing stops and cranes his neck to look back over his shoulder, like he's heard someone call his name, and for a moment that goes on roughly forever, he looks Stiles right in the eye – or possibly in the tonsils, because whoever he's looking at doesn't just look a _bit_ like Derek, he looks... he's _exactly_...

...he's turned around again, and he's vanishing into the wood on the northern edge of the field, and this is _not happening_ until Stiles has got to the bottom of whatever the hell is going on. He throws subtlety to the wind and _runs_ after the disappearing figure, sidling, shoving and apologising his way past whoever gets in the way, then hurling himself straight through the tree-line without slowing down.

Fifteen paces later, Stiles stops to stop to pull a stick out of his shoe and face the fact that there's no-one in sight and he doesn't even know if he's going in the right direction anymore. He rotates in a tight circle and listens to the melody of the songbirds mocking him from up in the branches somewhere, overlaying the more distant hum of the fair still going on without him.

"Anyone there?" he calls. "Hello?"

He's just considering the relative merits of giving up and heading back when he gets an answer.

"Alone in the woods, Stiles? You never know who could be lurking out here." The voice is definitely Derek's.

Stiles whirls in the appropriate direction, and has barely time to take in the shape of a an unmistakably _human_ Derek emerging from the shade before the distance between them is gone and he's being shoved up against the nearest tree and thoroughly kissed in greeting. Stiles swiftly puts aside the couple of dozen questions still burning in his mind for a minute or two, and makes use of the opportunity to get his hands on Derek's head and verify for himself that whatever sorcery is responsible for this, it passes tactile muster. Human-Derek has shorter hair than Stiles is used to; the naked skin of the back of his neck is right there for his fingers to find, and Stiles couldn't even explain why that thrills him so much.

When Derek finally finishes saying hello and leans back to a distance they can see each other properly, Stiles is still a long way from believing this is happening. " _Derek_?"

"Hello," says Derek. There is nothing unfamiliar about that smirk.

"You're wearing _clothes_ ," is the first proper sentence to come out of Stiles' mouth.

"Don't get used to it." Derek is obviously enjoying seeing Stiles flabbergasted, and Stiles for once is having a little trouble holding it against him.

"You – you're... is this something you can _do?_ " Stiles' research has utterly failed to prepare him for this.

"Surprise," says Derek. "Like it?"

"Oh yeah," Stiles breathes, nevermind that he's going to rip Derek a new one later for keeping this from him for so long – it's hardly like Stiles had never _asked_ if incubi could do something like this, even if he'd never quite managed to ask exactly the right question. "Why-"

"Tell you what," says Derek, before Stiles has got as far as picking which 'why' he wants to start with, "you wait until after, and I'll tell you as much about this as you want to know. Deal?"

"Deal," Stiles agrees, feeling giddy as he reels Derek back in – and that's how he ends up with his tongue in Derek's mouth when, he hears a voice choke out the name, " _Stiles_?" a minute later, and realises it's Scott.

No-one bites Stiles' tongue when they whip apart, so there's that, at least. Scott has stopped a half a dozen paces away and is looking at Stiles like he's really honestly unsure if he might be mistaken.

"Uh. Hi Scott," Stiles calls. "Uh. This is Derek. Derek, Scott."

Derek produces the world's stiffest acknowledging nod. Stiles whacks him on the back of the head. "Hey, relax, alright? He's my friend." Derek responds to this friendly advice by tensing up a little further.

Scott responds by giving Derek the most uncertain wave in all of history. "He's not. Um. Bothering you, is he?"

"Oh!" says Stiles. "No. Oh no. Definitely not. No bothering going on here, right Derek?" Derek purses his lips and frowns. It's not his greatest moment of communication, but the general desire for Scott not to be here interrupting them more-or-less makes it across.

"If you could maybe give us a while," Stiles goes on, "I'll meet you back home... when I meet you."

Scott looks torn, but chokes out an "Okay," and turns to leave. "You... might wanna move a little further away from the field though," he offers.

"Thanks buddy," Stiles calls after him. "We'll do that."

The awkward silence stretches on as Scott's footsteps fade away into the background noise of the fair, carrying on without them somewhere in the distance.

"That was Scott," Stiles says helpfully.

"You want to tell him about us, don't you?" says Derek, sounding oddly far away.

"I think he's picked up the general gist by now."

"The _truth_ ," snaps Derek, louder, in the voice that has come to mean _don't-mess-with-me, I-can-read-your-desires_. Stiles' heart drops clean through his chest. It's not like he doesn't get why Derek would have to bring this up _now_ – Scott really has the worsttiming – but Stiles has put a lot of time and effort coming to terms with the sordid nature of their affair, and does Derek reallyhave to rub it in his face?

"Look, I get it, okay?" he offers, as gently as he can. "I knew what I was getting into when I-"

"Tell him," says Derek. Stiles is still gaping at him when he adds, "As much as you want to. I can trust a werewolf not to go running to the hunters with what he knows."

"But – I'm under a _geas_." Stiles is dreaming. This is the only way this day makes any goddamn sense. His subconscious doesn't even have the decency to be _subtle_ anymore.

"I'm releasing you from it," declares Derek, in the same flat tone.

Behind Derek's neck, Stiles pinches the back one hand between the nails of the other. The pain this produces is surprisingly convincing. "You can _do_ that?"

"My geas. I can do as I please." The thing about having this conversation in broad daylight from only inches apart is that Derek is looking Stiles right in the eye when he says it, and what Stiles can see in those eyes really doesn't leave any doubt.

This _isn't_ a dream. This isn't a trick. Derek meansit. And Stiles might just be the luckiest guy in all the world.

"Oh _wow_ ," he breathes, and tugs Derek back in so he can thank him properly. A little later, Stiles wrests his lips away long enough to add, "This does _not_ mean you get out of twenty questions later."

" _Stiles_ ," replies Derek. "I have _met_ you."

Stiles beams at him. "Sooo, before? Own up: you were waiting for me to give up and turn around before you pounced."

"Maybe." Derek's smile is sly, and only barely glimpsed before it vanishes under the fabric of his tunic as he tugs it off over his head, revealing Stiles' first ever sight of _human_ -Derek's bare naked chest.

Screw birthdays, fairs _and_ Christmas, Stiles is marking this date on the calendar and celebrating its anniversary every year.

* * *

According to Derek, a geas canbe amended, but amendments don't take effect until the dawning of the next new day. Whatever Stiles eventually decides he's going to say to Scott, it's going to have to wait until tomorrow morning.

Stiles, having already decided to tackle the situation with all the honesty and maturity he can muster, elects to weather the intervening period by avoiding Scott as much as their shared chore rosters will possibly allow, then refusing to go to bed until he hears the intermittent whistle of Scott's snoring through the cracks in the door. He tiptoes into their room with the exaggerated care. Nothing suspicious going on; he's just Scott's very good friend who happened to be caught by Scott _in flagrant delicto_ in the woods with a strange man, who can't _quite_ bring himself to look his good friend in the eye right now.

Stiles makes it across the room with the stealth of a mouse, and falls onto his mattress like an owl in the night – remembering just a littletoo late he'd left his bestiary sitting on the bed that morning, which falls from the shifting mattress to the floor with two hundred leather-bound pages worth of _thud_.

Somewhere in the darkness, bedclothes rustle. "Stiles?" murmur Scott, voice thick with sleep.

Stiles holds his breath, and doesn't let it out again until he hears Scott roll over and go back to sleep. He silently thanks all and any gods who may be still watching out for him, and solemnly swears they're going to have that talk first thing in the morning.

An uncertain passage of hours later, Stiles wakes from a vivid dream in which Derek is an alpha werewolf who keeps making goo-goo eyes at Scott and trying to get him to 'join his pack' (cough). The early dawn light is just starting to filter in through the windows, and he blinks his eyes into focus to see Scott staring at him from the end of his bed.

When he's recovered from jumping halfway out of his skin and running through most of his vocabulary of swear words, Scott at least has the decency to look sheepish. "Sorry. I didn't mean to startle you. I was wondering if I should wake you."

"Well I'm awake _now_." Stiles rubs the back of his neck. Sudden movements with sleepy muscles are no fun way to start the day. The silence between them stretches just long enough to start getting awkward.

"I didn't see you last night," Scott offers eventually. "Everything's okay, right?"

"What, with me? Yeah, buddy, everything's fine! Great! Fantastic! Fine!" Stiles winces, and quits before he can make it worse. The question is coming, he can practically feel it.

"So what's the story with, y'know, Derek?" It's pretty obvious Scott has no idea what the procedure is when you catch your best friend in a passionate embrace with a strange man in the woods but he wants to get it right, so even if he's unsure how many details he actually _wants_ , he's gonna default to supportive and curious. "I mean, if you wanna talk about it."

Stiles takes a deep breath, and says, "Yes, we're having sex, no, that wasn't the first time, and the thing about Derek, he's not so much _human_ ," before he can think better of it. That last part gets him an actual double take.

"What?" says Scott, then, "I _knew_ it! He, uh, he didn't smell right."

"I bet. You'd better sit down, it's a long story."

Scott plops down on the bed opposite, leaning eagerly over his knees. "So what is he? He didn't smell like a werewolf either."

"Okay," says Stiles. "Don't freak out. He's an incubus."

Scott freaks out. " _What_?!"

"I said don't freak out!"

"I saw you yesterday with a life-sucking demon and _I'm not allowed to freak out?_ "

"Yes, alright, in retrospect asking you not to freak out was probably a bit much, and I know how this sounds, but hear me out, okay?"

Scott takes his seat again very slowly, as if worried Stiles might sprout horns if he makes a wrong move.

Stiles takes another deep breath. "You remember the night I set myself up as bait after the incubus attacked Lydia? Not Derek, obviously. The _other_ incubus."

"The one you killed, right?"

May as well start there as anywhere. "Right, except _not_ exactly right, because... I might have mislead you about some of the details about what happened that night."

Scott looks understandably puzzled. "I thought you said an incubus couldn't – you know – with a man?"

Stiles winces internally; he'd been holding onto the hope Scott might have forgotten about that bit. "Yes, that's what I said, only it turns out that whole story was one big, steaming pile of horse-poo and the truth is incubi are _really_ not that picky and I was stupid ever to believe it to begin with, and if you could promise never to raise that subject again you'd be doing me a big favour."

Scott's eyebrows do an interesting little dance. "But... in the morning, it was dead."

"Yeah," Stiles agrees.

"So... what _did_ happen?"

" _Derek_ happened," Stiles tells him. "He was tracking the incubus that attacked Lydia, and he ambushed it right on the windowsill and killed it, then he climbed inside and made me promise not to tell anyone what really happened."

Scott has never been the sharpest knife in the armoury, but he spots the gap in this account pretty quickly. "But... why?"

Stiles shrugs helplessly. "Apparently Derek doesn't like it when other incubi show up in his patch and making a big show out of murdering innocent young ladies and attracting lots of attention. I think he's been living around here for ages, just keeping his head down so the hunters don't catch on he's here. Which was going a lot better for him before he had that genius idea of going for _Kate_ , but then-"

"Wait, _Derek_ was the incubus that attacked Kate?"

"And trust me," Stiles tells him, with fervour, "I am _never_ letting him live that down, but for what it's worth, I'm pretty sure he wasn't going to kill her. If she hadn't been a hunter, I think she'd have just woken up in the morning and written it all off as a dream. I mean, _I_ nearly did that the first time, and I was expecting him! It's how he keeps from getting detected without having to kill anyone."

Scott wrinkles his nose. "That's still kinda..."

"I know, I know, but what else is he supposed to do? He'll _die_ if he doesn't get sex – don't even ask me to explain how that works, it's a whole other subject – but it's not like he can just settle down with just anyone without being found out sooner or later."

Scott looks like he's trying to find the flaw in this logic. "How much... _sex_ does he need? Is he – you know – still doing that with other people?"

"I don't think so?" Stiles hasn't ever really asked, is the truth. He's been more concerned with whether Derek might be killing people than whether the literal sex demon he's sleeping with might be cheating on him. He's not really sure how he'd feel about it if Derek was. "With the hunters and everything, he's been trying to lie low. I've been helping him keep out of sight."

"I thought you just helped the hunters _kill_ an incubus," says Scott, looking more than a little scandalised.

"Yeah," Stiles admits. "So did they."

There's silence as Scott tries to digest all this, and Stiles tries very hard to give him the chance to.

"Stiles," Scott says at last, his tone careful, "you have to know this all sounds really bad. You're the one who _told_ me how they can mess with your mind – you said they can make you do or believe anything they want. How do I know that's not what's he's been doing to you all along?"

"You don't." The words fall out of Stiles to land like lead weights. " _I_ don't. And don't think I haven't thought about it – I have, I _really_ have. But it's not like he's ever got me to _do_ anything more diabolical than keep him secret, and like I told you, he saved my life! I owe him that much!"

As rationales go, most of this sounded better in Stiles' head than it does once he can see the effect reflected in Scott's face. Scott doesn't look like he's buying any of it. "You just told me he's been forcing himself on people in their sleep for years, and you're just okay with that?"

"Well, no, but what does it matter?" Stiles has the horrible feeling he's losing control of this conversation. "There's no 'forcing' required, okay? Last time I accused him of that he came over all insulted by the idea he'd _need_ to force anyone."

"Stiles, why are you asking me why it matters?" Though Stiles' voice has been rising with every word, Scott remains terribly collected as he says, simply, "You _know_ why it matters."

"Is this about Allison? Kate was a dumb fluke, Scott, and I'm pretty sure he's smart enough not to make a habit of hitting on hunters." Not that Allison isn't the perfect target – the youngest and least experienced of the hunters, Kate's favourite. She'd be the ideal target for some backhanded revenge. But Derek wouldn't do that. Would he?

"It's not just about Allison," Scott insists. "It's about Lydia too – you didn't _see_ what she was like when she woke up, Stiles – and everyone else he's done this to, whether they thought it was a dream or not. That doesn't just make it all go away!"

Stiles opens his mouth to object. Then he closes it again, and actually stops to think about what Scott's been saying, and with it, the terrifying possibility that the guy might actually have a point.

The thing about Scott, even if he's never been the smart one, is that he's well intentioned to a fault. He learned to align his moral compass around the same time he had to watch the village preacher talk his mother into following her 'duty' back to her husband _three times_ before that bastard son of a bastard finally left her himself, and left town for good. Since then, Scott's given up listening to supposedly-educated authority figures trying to guide him between right and wrong, and started listening to his heart and gut instead. They don't often lead him wrong.

And thinking about Scott's mum only goes and gets Stiles thinking about how they never _did_ get to go see her before they left for Beacon Fell, because Scott blew his last chance while he was helping Stiles find a monster to blame for a suspicious death, because _no-one_ in their right mind would have taken Derek's innocence at his word otherwise. She's been living the lonely life of the village midwife ever since her husband left her like that, and god – of _course_ it's not just Allison Scott would be worried about. With that crack about 'the unhappily married', Derek as good as _told_ him Scott has every reason to worry about who else might've had a late night visit from the likes of Derek over the years.

Scott's no saint: push him the wrong way, and he's one of the most bull-headed people Stiles has ever known – you only needed to see him around Allison once to see just what tunnel vision looks like. But sometimes, tunnel vision might be exactly what you need to show you just how little weight your excuses ever carried to begin with.

"Oh, god." Stiles sits down heavily and looks at his hands. "Can't we go back to you yelling at me and running off to make a bad decision involving Allison and the full moon? I'm better at doing that argument."

He watches Scott shrug back at him and offer a half-smile of what might be apologetic character. "I think it must be my turn to be the one to stop you running off to make a stupid decision. Not that I think you're stupid," he clarifies, quickly, "I just – I just don't want you to get _hurt_. Even if Derek hasn't done anything he shouldn't yet, that doesn't mean he's never planning to make you do anything you wouldn't want to."

_I don't think he's smart enough to plan that far ahead_ , isn't an excuse that works very well if you haven't _met_ Derek."I know. But what I keep coming back to is if this is all some big scam to get me on his side, _why_? Why me? What have I got that's worth anything to a demon?"

"There's the stuff Deaton's teaching you," offers Scott, shrugging some more.

"Sure," laughs Stiles. "An apprentice so green he bought the story that you can kill an incubus by making it touch a dick. There's a real catch." They should _both_ get a good laugh out of that one, but out of the corner of his eye, Scott's frowning again.

"What if this is the one window where he could get to you? After you've started training, but before you know enough to know better."

Stiles feels his stomach lurch. "I _did_ help him fake his death to throw the hunters off his trail," he admits. "And you remember how I found that trick to let you through the mountain ash? He was the one who taught me that, and I used it to let _him_ in too."

"Stiles?"

"But I didn't just let him in for nothing," Stiles insists. "I made him promise never to harm anyone here, and he did!"

"You think he's gonna keep that promise?" says Scott, missing the point entirely.

"He _has_ to! When you make a deal with a demon it forms a geas – he couldn't break it now without tearing himself apart. Same as when he made me swear never to tell anyone about him – knocked me cold first time I slipped up."

Scott's mouth moves silently for a moment, in the manner of so many people trying to follow Stiles' train of logic. "Aren't you... telling me now?"

"Only because he changed his mind today. Probably figured my werewolf-best-friend had to be the _last_ person who'd go running to the hunters. And now you know, and you – you're asking me _all_ the questions you should be. That means something, right?" Stiles desperately needs it to mean something, and he needs Scott to understand it, because he doesn't know how to explain this otherwise. How he knows there's always that chance Derek's been playing him, but he thinks he'd rather be the guy who falls for the con than the one who goes through the rest of his life never trusting anyone who comes without a royal commendation. That he's in way too far to get out of this cleanly, whether Derek's for real or not.

"I guess." Scott sounds a long way from sure, but he's definitely trying to see this Stiles' way. "Maybe you... I mean, it wouldn't be the first time the hunters have been wrong about this stuff, right?"

"That's what I keep telling myself," says Stiles, fervently.

Scott shifts uncomfortably. "Can I, uh, meet him?" he asks. "Derek, I mean – properly."

"We didn't really talk about that," Stiles admits, but it's the obvious next step. "I don't see why not."

Scott nods, then turns a little green. "I'm not gonna. Um. Get the mad urge to, like. Uh. Jump him. Am I?"

Stiles has to stare at Scott a moment before it clicks. "Oh. _No_. No, no. He doesn't... have that effect on everyone – he's been walking around the festival all day with his human face on and no-one's jumped him yet, so. Besides, that stuff isn't supposed to work on werewolves."

Scott looks visibly relieved. "But it works on you?"

Stiles holds up his hands. Scott seems to accept this.

"So..." he says, a moment later, voice pitched low and curious, "what's it like?"

"What's what... _oh_." Yep, Scott just asked him that.

"Is it... y'know, is it like what they say?"

"What they say it's like," says Stiles, "does not even come close to doing justice to what it's really like."

"Whoa," says Scott.

" _Whoa_ ," Stiles agrees.

* * *

Since Derek has made it clear that finding someone in a crowded marketplace using only his ill-defined mind-reading skills is more trouble than it's worth, Stiles is supposed to meet him in the morning at a stall just to the left of the big oak tree on the south side of the field. Ranked on a scale from 'demon-blood-dagger-rituals' to 'lying-without-lying about where you were last night to your werewolf-best-friend', meeting at the markets _ought_ to be a refreshingly normal change of pace for their relationship, but now Stiles is here waiting, the enormity of the knowledge he's meeting a demon-in-disguise in _public_ will not leave him alone. The odds he's not already projecting 'clandestine meeting' to all and sundry are looking pretty dismal, going by how the guy sitting up on the wagon behind the stall has been looking at Stiles for several minutes now like he can see right through him and finds it hilarious. What this means is that Stiles is feeling thoroughly twitchy and nervous even _before_ he spots Chris Argent heading for the guy hawking snake oil from the stall opposite, and panics.

From where Stiles is standing, it's difficult to guess whether the trader is in more danger of being taken away for conning the locals out of their hard-earned coin with bottles of sugar water, or whether he's about to be charged with performing actual witchcraft. Either way, Stiles is experiencing a pressing need to _not_ be here when it happens – a need only slightly beaten out by the need not to be seen leaving the scene in a hurry right beforehand, which leaves him trapped in useless indecision while the chance to make a move slips away. As a compromise, he settles on feigning sudden and consuming interest in a hanging bolt of embroidered cloth at the nearest table in his best attempt to look inconspicuous, though considering that the guy on the wagon seems to have just progressed to inviting someone else over to share the joke, he's probably failing miserably. Under the circumstances, Stiles thinks he really ought to be forgiven for failing to notice that the explosion he was expecting _hasn't happened_ until Chris has been calmly negotiating with the trader for several minutes.

Much delayed, it finally occurs to him that there's a _third_ option for what Chris is here to do, and if a hunter is purchasing supplies from an apothecary who's been loudly touting the properties of his selection of 'Mystical Herbs from the Far East', now would be a really good time to take note of exactly what those 'mystical herbs' might be.

He edges around his hanging cloth and peeks past, granting him the sight of Chris still deep in negotiation with the seller, though whatever's being said is lost in the noise of the crowd. He's debating the relative merits of throwing out all subtlety and marching over there to pretend like he's just run into Chris by accident (which isn't even far from the truth, give or take five minutes hiding behind a curtain like a pantomime villain) when his limited view of Mr Argent suddenly transforms into a distressingly _good_ view of someone's ample cleavage, leaving Stiles to do the kind of stunned double-take that is probably not going to do his case any favours about ten seconds from now.

Stiles wrenches his gaze northwards, and discovers the owner of the cleavage is a distressingly attractive young blonde girl in a dress which almost certainly hadn't been cut that low by accident. His first defining impression is that she has incredibly red lips and too many teeth, bared at him in a grin that sets off several non-specific danger signals in the back of Stiles' mind. "Seen something you like?" she asks, in a voice that drips with double meaning.

"I was just looking at the, ah," Stiles gestures vaguely in the direction of the bolt of fabric which has been allegedly holding his attention since he first spotted Chris heading his way. "It's. Bound to be more than I can afford anyway, don't worry about it, I'll just get out of your way." Stiles makes to go only to find that she's still inexplicably in his way.

The girl gives a fluid shrug. "There's never any harm in asking. You might be surprised." Her long hair has been plaited into a delicate braid which hangs over her shoulder to dip into the curve of her supple bosom in a manner Stiles finds horribly distracting.

Stiles is not in obvious mortal danger; his life does not flash before his eyes. However, in his heightened state of panic, a number of thoughts do flash through his mind in quick succession. In order, they go roughly like this:

  1. She’s flirting with him.
  2. She’s trying to sell him something.  

  3. Though there’s also more-than-tiny chance she’s noticed his shifty behaviour and thinks he’s trying to steal something.  

  4. Whatever the case, there’s no way she’s going to let him extricate himself from this situation gracefully, and explaining that the truth is that he’s only here to spy on a guy across the way is going to do him no good whatsoever.  

  5. People this attractive do not flirt with Stiles, not even when they’re trying to sell him something.  

  6. No really, what’s even going on here?  

  7. Should Derek show up right this moment, Stiles has no idea how he’s going to react to finding him flirting with a beautiful girl. Does Derek do jealousy?  

  8. Actually, unless Stiles is completely misinterpreting Derek’s reaction to that thing where he almost walked in on Lydia with Jackson that one time, he’s pretty sure Derek does do jealousy.  

  9. This is completely not the time to start thinking about how hot Derek is when he’s jealous.  

  10. Did the words ‘subtle curve of her bosom’ seriously go through his mind a minute ago? The hell?  

  11. Even though no-one flirts with Stiles, there’s something about this terribly attractive woman is flirting with him that’s horrifyingly familiar in a way he can’t quite pin down.



"Oh my _god_ ," Stiles exclaims, remembering almost too late to tone his voice down to a conspiratal hiss, "you're a _succubus_?"

The succubus gives him a wicked grin and exchanges looks with the guy on the wagon, who's openly grinning too with the same feral pleasure. "And you're..." Stiles stammers, seeing said guy in a horrible new light. "You're _both_...?"

"He catches on fast, doesn't he?" says the incubus sitting on the wagon.

"He _does_ ," the girl agrees. "I think I'm starting to see why he likes you so much," she adds, winking at Stiles.

A shadow falls over the girl's shoulder. "Erica, _behave_ ," says Derek, to Stiles' incalculable relief and great confusion.

'Erica' doesn't let being caught out put her off her stride. "I was just saying hello," she says, stepping – or possibly flouncing – aside.

"Aren't you always," says Derek. Stiles looks back and forth between them with his mouth unhinged.

"Will someone tell me what exactly is going on here?" he hisses.

"What's wrong?" says the other incubus, hopping down off the wagon. "Never seen a travelling merchant operation before?"

"Stiles," says Derek, evenly, "Meet Isaac and Erica."

Stiles looks from Derek to Isaac to Erica and back again. "There's _three_ of you?"

"Four," says Isaac, "But Boyd's off haggling with the blacksmith. We threw an axel halfway from the last town, and it turns out wagon parts don't so much grow back like some of us."

Everything here is starting to come together to form a picture Stiles is quite epically unprepared to deal with. "Why didn't you _tell_ me about this?" he complains to Derek, shocked and betrayed in a way he hasn't felt since finding out he'd slept with someone who thought _Kate Argent_ would make a good pull.

Derek gives him a look. "'By the way, Stiles, contrary to what you seem to believe, I _don't_ spend all my time lurking underneath the windows of the young and innocent. When I'm not tracking rogues halfway across the country, I waste most of my life on the merchant routes playing mentor to a small travelling circus.'"

"Okay," Stiles concedes. "I admit that would have been a bit of hard sell." The wagon really does look like it's seen better days. From here, Stiles can make out what is almost a piece of dried horse-dung stuck to one of the wheels. "You realise all the romance and mystique has gone from this relationship. _Gone_."

Derek gives him another look. It's a look that suggests there is so much wrong with what Stiles just said that Derek doesn't even know where to start, and resents being made try to figure it out.

"What's all this _for_?" Stiles tries.

Isaac shrugs. "In a lifestyle like ours, it pays to stay on the move."

Stiles can feel something like hysteria bubbling in his chest. "The same lifestyle that just planted you not twelve feet away from where _a hunter –_ who has been tracking you for _months_ – is right now buying _magical supplies_?"

He'd swear he actually feels the temperature drop as the three of them catch on.

"A hunter?" says Derek.

"Where?" says Isaac.

Stiles thumbs a finger over his shoulder. "Where do you think? The apothecary, right there." Chris is gone when Stiles turns to look for himself, but he does just catch sight of the man vanishing into the crowd. "And it looks like he's done, without even noticing the little convention of demons going on right under his nose. It's like I'm stuck narrating a crazed romantic tragedy of near misses over here."

"What was he buying?" asks Erica.

"I don't _know_ , that's what I was trying to see when you came over to say 'hi'," Stiles tells her. "Bit late now."

"We can work with that," says Derek. "Is that who he was talking to?" He points to the trader, and Stiles nods. "Erica, why don't you go find out?"

Erica smirks at Stiles' expression, and stalks over to talk to the medicine seller. Stiles watches her go. "Is she going to...?"

Derek loops an arm around Stiles' shoulders. "Still want to know what it's like to be put under the thrall?" he murmurs in Stiles' ear. "Keep watching."

Stiles can't make out what they're saying from this far away, but he watches Erica put a hand on the man's arm to get his attention. Though she's facing away from him he has a pretty good view of how the guy reacts.

"Looks like a grown man falling over himself because a pretty girl half his age batted her eyelashes at him," he decides. He wonders vaguely what this says about how much satisfaction the man is getting out of his normal sex life, and how much incubi or succubi can tell about a potential mark from a distance. If they've all got looks as head-turning as Derek and Erica, probably quite a lot.

In his ear, Derek whispers, "You were expecting more?"

"Well, yeah. She could make him keel over unconscious and sleep like the dead until she wakes him up again, right? That's going a _little_ beyond flirting."

"She could make him murder his own brother if he's susceptible enough," says Derek, rather too calmly for Stiles' comfort, "but then, people have done worse for love."

"For _love_ ," Stiles counters, "not for girls they just met."

"You'd be amazed how much trouble people have telling the difference sometimes," says Derek, like this is actually an insightful observation or something.

Stiles shifts uncomfortably. Thinking about sex or love around Derek is not a clever thing to do in public. "Is she going to have to... you know, have sex with him?"

Derek chuckles softly. "That bother you?"

Stiles tries to think of an answer more nuanced than, _he doesn't seem like her type and it wasn't even her idea_. "I don't know, aren't you supposed to avoid mixing business and pleasure?" Possibly this is the wrong thing to quote to an incubus. Possibly this is _especially_ the wrong thing to quote to an incubus who's fielding your questions while draped over your shoulder and breathing on your neck.

"She doesn't have to have sex with him unless she wants to, Stiles," says Derek. "Happy?"

"Okay, let me rephrase," says Stiles, carefully. "Is he going to shrivel up and die within seven days if she doesn't?"

"We can release someone from our thrall peacefully, Stiles," Derek assures him. "Whatever you've been brought up to believe, you'd be amazed how final and devastating encounters with us _don't have to be_ in reality."

Stiles takes a shaky breath. "I've been picking up that theme, yeah. You realise this devil-on-my-shoulder act hasn't intimidated me in ages, right?"

"As if intimidating you was ever my objective," says Derek, sounding pleased with himself. Before Stiles can make up his mind whether this would be a completely terrible moment to drag Derek off into the bushes, Erica comes back looking pleased with herself.

"Well?" Derek prompts.

Erica brandishes a slate covered in chalk, the kind a lot of merchants use to tally prices. "He gave me a list."

"Isn't he gonna want this back?" asks Stiles, throwing the shop across the way a nervous glance.

"Said I could keep it," says Erica, looking terribly smug.

Stiles looks down the list, then up at Derek. "Anything on here mean anything to you?"

Derek takes the tablet from him and frowns at it. "The first two are foreign varieties of wolfsbane."

"Varieties that do what?"

"Other than irritate werewolves? No idea, nothing I ever bothered to memorise. Though I imagine your wolf friend will see it differently."

"You think?" says Stiles. "Oh, speaking of Scott, he knows about you now. Or at least the version that was up to date until _this_ happened."

That gets him Derek's attention back very quickly. "You told him?"

"You _said_ I could."

"I didn't know you _would_ ," says Derek, which is the sort of statement with all sorts of implications Stiles does not have time to think about. "How did he take it?"

"The news his best friend is sleeping with an incubus for months without the first shred of real proof he's not being secretly groomed for some nefarious purpose without his knowledge?" says Stiles. "Pretty well, considering. He wants to meet you now, by the way. That a problem?"

Derek looks more than a little startled, but recovers quickly. "No. Not unless you'd like it to be."

"Great, because I told him where I was meeting you today, and he's probably on his way here now." Stiles indicates the crowd in the general direction of the castle, and, as luck would have it, spots a familiar mop of brown hair bobbing in their midst. "Hey, speak of the were-devil. Wait here, I'll go grab him." Leaving Derek with the tablet, Stiles pushes eagerly away into the throng, just as Scott makes eye contact.

"Oh, hey, Scott – there's been some new developments..." is as far as Stiles gets into his explanation before Scott's grabbing him urgently and dragging him back into the crack between two wagons.

"When I was going past the blacksmith on my way here, this guy came out – it wasn't Derek and _he didn't smell human_ ," Scott hisses to him. "He came this way, I've been following him all the way here."

Something that wants to be a hysterical bubble of laughter gets stuck in Stiles' chest. "Oh, sounds like you already met Boyd. That's great!"

"Who's Boyd?" Scott looks utterly lost in a way Stiles can very much relate to.

"Good news, Scott!" Stiles gives him a friendly thump on the back. "You got here just in time to meet the whole family."

**Notes for the Chapter:**

> Trivia: There are actually a number of [Beacon Hills](http://en.wikipedia.org/wiki/Beacon_Hill,_Buckinghamshire) in the UK (which is to say, hills called Beacon _Hill_ \- the only use of Beacon Hill _s_ I have managed to locate using google and wikipedia remains entirely fictional). Most appear to be actual hills which served as part of a beacon chain used for very basic medieval communication, though some, unsurprisingly, gave their name to a nearby settlement. There's even a [Beacon End](http://en.wikipedia.org/wiki/Beacon_End) and a place called [Beaconsfield](http://en.wikipedia.org/wiki/Beaconsfield_%28disambiguation%29). But there are also a couple of real [Beacon Fells](http://en.wikipedia.org/wiki/Beacon_Fell_%28disambiguation%29). Though this story is not necessarily set near either of them (or even in 'real' medieval England at all, as opposed to some vaguely-defined pseudo-European fantasy country, the details of which may be tweaked at the author's convenience), I could hardly turn down the perfect excuse to use a name as wonderfully medieval sounding as Beacon Fell, could I?
> 
> Though I doubt Jeff Davis ever had anything remotely of the sort in mind, Beacon Hills (and related derivatives) conveniently turned out to be as appropriate a name for a fantasy-middle-ages-settlement as I could have hoped for. ;)


	9. Chapter 9

Logically speaking, there is no way introducing Scott and Derek should come _close_ to being the most nerve-wracking thing Stiles has done recently. It's only been a week since he had to watch Scott face off against a seriously irate pack of werewolves and a real (arguably) live volkodlak intent on sucking out his (Stiles') own soul. He's dealt with the unspeakable stress of that experience by partaking in some studious denial about just how close he'd come to getting eaten, plus some equally serious denial that the incident had any sort of symbolic or metaphorical relevance to the state of his life at large. Encouraging Scott to take on dangerous supernatural creatures should not ever become a habit.

The trouble with that theory is that it's awfully hard to both deny something and lean on it for some much-needed perspective simultaneously. There's no easy way for even Stiles to deny that Derek easily qualifies for the 'dangerous supernatural creature' category either. And if Scott and Derek don't get through the angry glaring phase of this introduction very soon, nostrils flaring in a way that suggests showing of teeth and growling could join the party at any moment, Stiles is going to arrive at a level of panic that would make even a volkodlak rethink its options for the afternoon.

There is no way this introduction is going to end well. There is no way to paint any individual aspect of this as going well, not unless you hail from some strange alternate plane of existence where 'introductions' is a word that means 'staring contest' and 'staring contest' implies 'an intense, mutual attempt to incinerate the other with your death glare'. He realises it was probably too much to hope they'd leap on this opportunity to bond over shared status as unfairly maligned supernatural outcasts with a mutual interest in Stiles' welfare and keeping the local hunter community off the scent – but since being introduced, Scott and Derek have so far done nothing else _but_ stare, and Stiles is beginning to panic.

Okay, so his internal monologue is probably over-selling the actual length of time the staring has gone on for – it's realistically more of a moment that's gone on slightly longer than moments are traditionally supposed to, but Stiles can get a lot of internal monologuing done in that sort of time.

Finally – _finally! –_ the cacophony of psychic messages Stiles has been sending seem to get through, and Scott shakes himself, settles slightly, and takes it upon himself to break the silence. "Stiles says you saved his life."

Internally (well, maybe just a little externally), Stiles cheers. Scott had even had the goodness to sound just a little tentativeabout it – like he's remembered they're supposed to be playing nice.

Derek says, "Not intentionally," tossing that lifeline right off the edge of the mountain as quickly as possible before settling down to ignore Stiles' vehement gestures to communicate that this is the kind of perfect honesty this conversation can get by without. "But I can promise you the incubus I was tracking that night would have killed him if I hadn't got to it first."

Scott looks mildly, honestly confused. "Then why _did_ you do it?"

Derek gives a short, impatient sigh. "Do you know why the hunters think there are no incubi, no succubi, in this part of the world? No-one sees us and we don't leave bodies behind. _He_ ," a violent jerk of his chin indicates the other incubus, "and I disagreed on that principle. Violently."

Scott considers this. "Is that the only reason you don't kill?" he asks – forget lifelines, that question is weighted with lead.

"Isn't it reason enough?"

"So," says Scott, "what are you doing with Stiles?" The crease of Scott's brow looks to be settling in for the afternoon. This is plainly not how he expected this conversation to go, and Stiles can relate.

Derek actually _smirks_. "Really?" Goddamnit, he's gone and chosen to interpret that question in the most sordid possible light. "How much detail do you want?"

"I don't want _any_ detail." The impatience in his tone suggests Scott may be only a little short of stamping a foot. "I want to know _why_. Why Stiles?"

"This isn't something I planned on, Scott. It just happened."

"Then why are you still doing it? He's living in a tower full of hunters, isn't that exactly what you're worried about?"

Derek breathes out, mirroring Scott's impatience. "Everything we do in life is a risk. Eventually you have to decide which risks are worth it."

"So you're saying... Stiles is worth it?"

Derek lets out a huff to the side then returns to levelling that steely gaze at Scott.

"Stiles told me he's been helping keep the hunters away from you," Scott offers, but Derek, being Derek, take that and twists it back around his neck.

"Interesting, he told me he's done the same for you. Should I be suspicious about the terms of your friendship?" Derek moves forward – hardly a fraction of a pace – but alarm bells are going off in Stiles' head even before the warning flash of gold in Scott's eyes, and the answering red in Derek's. This could be about to go really bad. Stiles is going to have to intercede. Stiles is going to have to get right in there between them before this gets ugly. Stiles is-

"Stiles," says Scott, "can you leave us for a minute?"

"What? No!" protests Stiles. "Anything you have to say to each other you can say in front of me. Right, Derek?"

"Actually, I agree with Scott." Derek says this without breaking eye contact.

"You _what_?"

"Stiles," says Derek. "Humour me. Please?"

The 'please' does it. Stiles stalks back to the wagon and drops himself down into the grass on the far side, busily assuring himself that he's being paranoid. There are bound to be plenty of perfectly good reasons why Scott and Derek might prefer to have this conversation with him out of earshot, right?

Several minutes of waiting later, he's managed to come up with exactly two: _with him gone, it'll be much easier for one of them to rip the other's throat out without witnesses_ , and _Stiles' presence can't distract either of them with the animalistic urge to pee on him to mark their territory_. He's still feeling far too peevish to try for something more complimentary.

The interim silence from Scott and Derek's direction is somewhat reassuring, if only because Stiles is fairly sure they couldn't actually murder each other without making themselves heard. By the time Scott emerges from the woods, first and alone, Stiles is mostly past abject terror and busy being generally furious with both of them.

"So?" There's no hiding his nerves. He doesn't feel like any part of that went well.

Scott shrugs. "I don't know. He's not what I was expecting."

"Tell me about it," breathes Stiles.

"He doesn't seem all that demonic. More... I don't know..."

"Sardonic?"

"I was gonna go with 'defensive', but yeah. Is he always that hard to get answers out of?"

Stiles laughs. "Scott, my friend, that was Derek on a _good_ day."

Scott shrugs a shoulder and shifts his weight. "It's just... if he had some big plan for you, wouldn't he have a better cover story?"

Stiles breathes out. "That's what I've been hanging on for months." A thought hits him. "Could you read much off him, with your werewolf senses?"

Scott shakes his head, apologetic. "He hardly smells like anything, and his heartbeat's steady like a clock." He starts to say something else, opens his mouth, then closes it again. "You like him?"

Stiles gapes at him. "Huh? Scott, me and Derek – you _know_ what this is about. You know what we're doing, do not make me spell it out for you."

"Yeah," says Scott, with infinite patience, "but, do you actually _like_ him?"

Is that what Scott wants to hear? _Does_ he 'like' Derek? Is that in any way a truthful statement about what passes for their relationship? Stiles gives in, and gives Scott the one answer that he can't possibly find a lie in. "I don't even know most of the time. Why?"

Scott shrugs one shoulder, expression unreadable. "Because I think he likes you." There's a space after that statement where Stiles could and should have grabbed Scott and made him qualify what the hell he even meant by that, but Stiles wastes it gaping at him some more, and the next thing he knows, Isaac is has appeared out of nowhere and is saying, "So, a werewolf, huh?" and Stiles' chance is gone. He's halfway grateful, if anything.

* * *

Derek emerges from the woods about a minute after Scott's gone off after Isaac, which is obviously no accident. "You kids play nice?" Stiles calls.

Derek tugs him behind the wagon and drops his forehead on Stiles' shoulder, which adds up to precisely nothing he was expecting, but okay. "The things I do for you."

"I have it on pretty good authority I'm _worth it_ , somehow or other," Stiles tells him, wondering if he should maybe pat Derek on the back or something. "Seriously, that bad?"

"The need to drag you into the woods and strip you bare is very hard to resist right now."

Stiles realises he's down with that idea on levels he'd not predicted. "Why resist?" Automatically, he throws a look at Scott, but he and Isaac seem pretty occupied with what may be the world's first werewolf/incubus arm-wrestling match, so it's not like Stiles will have ditched him blind or anything.

A startled jerk from Derek quickly melts into a grin. "Isaac," he calls, "keep an eye on the stall for me," and takes Stiles by the hand.

* * *

Evening finds them huddled together on the village green, not so close to the bonfire as to make themselves obvious, but close enough to enjoy the glow in fading whispers of warmth whenever the breeze gusts their way. They're not alone. There are musicians, and dancing, and drinking in whatever form a reveller has the coin for – all the town is out to celebrate the closing of the fair, and every traveller or merchant who isn't already getting an early night with two day's new wealth packed flat beneath their bedrolls are out to join them. It's too early in the season for the winter chill to have entirely lost the stamina to set in early; this far from the fire the cold can get at a body from three directions out of four, but snuggled into the space between Derek's legs with his chest pressed to Stiles' back, Stiles can sit comfortably and pretend, for the one night in the year where they can be semi-seen in public without fear, to be no different from any other couple, old or young out here doing the very same thing, basking in the firelight.

Somewhere out there, Lydia is probably making a show of deigning to accept a dance from Jackson, who'll spend the whole song smirking like he invented it, and the only saving grace about it is that they're doing it somewhere out of sight. Allison's probably not going to make it out of her father's sight all evening, more's the pity – not unless her aunt runs interference on her behalf – but Isaac and Scott seem to have hit it off since whichever of them won that arm-wrestle earlier, and are sitting with their knees pulled up on the far edge of the firelight in deep conversation. Erica vanished out of the light altogether with a young man a little while ago, while Boyd has been dancing such a vigorous jig with a girl in a blue dress that she's broken one of her shoes, and has accepted a chivalrous offer to be carried home like a princess with some satisfaction.

If you didn't know they were all demons, it would all be so normal that the thought makes Stiles' throat hurt.

"Your image is never going to recover," he tells Derek, seriously. Even the old village Rector would have had to work to make the idea of sneaking off with an attractive stranger at the spring fair sound seriously sinful. By local standards it's practically the height of romance.

"It's not always like this, you know," says Derek.

"No?"

"Some days, it takes _hours_ of lounging in the corners of merchant taverns before we meet anyone interesting," Derek tells him, equally serious. "On a bad night, we might even have to buy our own beer."

"Isn't there even a _little_ bit of sneaking in through windows in the middle of the night?"

He feels Derek chuckle into the back of his neck. "You'd be amazed how often it doesn't come to that."

"Uh-huh." Yeah, not _that_ amazed – he does have eyes. Even after months of Derek's best efforts to rid Stiles of every last shred of magical-virginity, Erica had very nearly turned his brain into mush in fifteen seconds flat. Even Isaac had Stiles' attention before he'd done anything more than be stupidly attractive and snigger at him behind his back. "So, for the record, roughly _how_ often do you get run out of town for lewd and sinful behaviour, corrupting the good nature of our youth?"

There's a faint rustle of fabric as Derek shrugs. "Usually not until we're on our way out anyway."

"Right. Of course. Where did you even find each other? Is this a 'birds of a feather' deal? A demon thing? Did Boyd just pop out of the woods one day and say, 'hey, lets all be demon buddies'?"

Derek stifles the beginning of a laugh. "Boyd's not a demon, Stiles, he's fae. Well, half-fae."

"He's what? But I just saw him and that girl, they were – there were _eyes_ being made there-" Stiles twists to find that Derek has broken into a particularly wicked grin. " _Oh_. Well. Why not? I'm sure fae have _needs_ like the rest of us. Must feel like you have a lot to prove, with the rest of you around." He's halfway settled back down when the obvious hits him. "Wait, you sent a _fae_ to the blacksmith?"

"Of course. He can tell good iron from bad at ten paces."

Stiles doesn't think he wants to know how that works. "The rest of you can't just – do your _thing_ with Boyd? The whole demon-sex thing?"

Derek shakes his head. "No. It has to be with a human, or it doesn't work."

"What about werewolves?"

"I don't think so," says Derek, thoughtful. "Never tested it. Though I wouldn't put it past Erica and Isaac to try."

Across the field, Erica has rejoined Isaac and Scott. Stiles wonders franticly whether he should be sending Scott a warning. Then he wonders something even worse. "Oh my god... they're not _your_ kids, are they?

"No." Derek doesn't bother to stifle this chuckle. "If we were fertile with humans, half the country would be demon by now."

While this is intensely reassuring, it raises more questions than it answers. "Then where do baby incubi come from?"

"Do _you_ remember being born?" Derek asks. Stiles thumps him.

"Come on, you must have _some_ idea."

Derek hesitates long enough to give Stiles the impression this is not a topic he's about to tackle lightly. "It's different for everyone. It takes... particular circumstances. Someone young enough that they haven't finished growing into their own skin – a stillborn baby that starts breathing just as everyone gives up hope... a dying child whose heart starts beating again; another death in the same house, or a grieving parent who wishes a little too hard for a miracle – just enough to summon the wrong kind of magic at the wrong place and time." Derek's breath gusts soft and cold at the back of Stiles' neck. "Sometimes it's something else that comes back in their place."

A faint chill settles at the base of Stiles' spine. He _knows_ this – demons _by definition_ don't have bodies of their own like humans do. He's heard the hunters trade enough stories of men possessed who spoke in tongues and tore through the very walls of their cells with the strength of a dozen men – some of his books explain even werewolves to a very specific kind of demonic possession, by something more animal, more savage than human. "So you're possessing the body of a dead person?"

"It's alive as long as I take care of it. Same as yours."

"How long until the – the _sensation_ thing kicks in?" _How long until you have to start having sex to not die_ would be a more accurate way to put that, but is a little too indelicate for even Stiles' broad sensibilities.

"Usually not until we've finished growing," Derek explains. "It comes on you gradually. You grow up knowing you're not like other humans, but it can take time to make sense of what you need to hold onto yourself. If you're lucky, another of us will find you before that happens."

"Do the parents... know?" Derek had parents. _Human_ parents. Stiles doesn't know what to do with that.

Derek shifts at his back. "Not to begin with." The sentence hangs in the night between them, before Stiles, reluctantly, picks it up.

"But they figure it out?"

There's a pause before Derek makes any reply, a little too long. "Isaac's father used to beat him. Tried to beat the evil out of him. Erica began having fits, when her body started to reject her, not long before we found her. They figure it out."

What Derek doesn't say rings even louder. Was Derek 'found'? Was there anyone to find him? He doesn't want to know how many people _die_ when a young succubus or incubus is 'figuring out' how to keep their own body from throwing them out. How many people came how close while Isaac or Erica – while Derek – were still learning how much sensation was enough?

"We were the lucky ones," whispers Derek, who can _read Stiles' desires_ , but if that's a peace offering, truth or polite fiction, Stiles is in no state to examine it. 'Normal' has never felt further away.

Stiles takes a deep breath and asks – finally – the question that's been hanging over the whole affair since this began. "So you guys are leaving after the festival?"

"That was the plan," replies Derek, but before Stiles can even begin to unpack all the implications in that, he adds. "You could come with us, if you like."

Stiles' stomach drops. Or fills with butterflies with wings of lace and metaphor. One of those things. Derek had _asked_. "I. Wow. I. I couldn't. I, just – Scott, and everything here, I couldn't just pack up and leave like that."

Derek shrugs it off. "Scott could come too. He'd fit right in."

"He'd never leave without Allison." It's the shortest and most obvious of a thousand different objections. "And Allison wouldn't leave."

There's silence from Derek for a moment, heavy and pregnant with meaning. "Stiles," he says, at last, in a tone that suggests this wording has been considered long and carefully, "you may not feel like you understand quite what this is between us yet, but I can promise you, it's been a long time since this was something I could have walked away from."

Stiles and the butterflies digest this, in all its layers of meaning.

 _That_ was _the plan_ , Derek had said, and the butterflies speed up a notch.

* * *

At some hour or other, people eventually stagger home – to their own beds or other people's, as their luck may have it. Not everyone has the luxury of a lazy start on the morrow, but Stiles, being acutely aware of their steward's propensity for leaving festivals in the company of some pliable young thing half his age and skulking home only when it suits him, makes it to bed fairly confident of the odds Harris _won't_ be around to pry them out of bed at first light. This turns out to have been a safe bet; the sun is well and truly up by the time he wakes, tired, but with a disarming buzz of optimism still thrumming through his veins in the wake of last night, which may or may not yet turn out to be indigestion. The hunters are making some sort of distant racket in the hallways, which probably means they still haven't found Harris yet, and are taking on the cause of the order of the household with all the self-righteousness they can muster.

They _have_ found Harris, as it turns out. Stiles' vague foreboding of indigestion reaches a violent climax when he sets foot in the main hall and his eyes on Harris' lifeless body, looking every bit the picture of prolonged, agonising death the hunters had so vividly described after discovering the last victim.

Rebecca, Lydia's maid, is found in the same state in the stairwell, face-down with her arms outstretched, as if she'd been in the act of fleeing upwards even as she was overcome.

No-one rightly knows what hour either of them arrived home last night, whether together or separately – or, indeed, whether after or before the several other residents who may quite well have managed to walk right by them in the dark.

* * *

In the excitement of the fair, most of what the Martin household so dutifully packed and loaded for the journey had yet to be unpacked, or in some cases unloaded from the carts at all, and thus the reloading of the carts is, this time, complete by noon. Ordinarily, the stay in Beacon Fell would be half the year, but the castle is far too large for mountain-ash rings and far too sparsely guarded in these frugal times to be defensible. By comparison, the Tower is a fortress.

Stiles has already reread his bestiary's entry on volkodlaks three times, and the significantly longer ones on both traditional vampires and werewolves once, and found exactly nothing in any of them to tell him what makes werewolves start rising from the grave, or whether they hang around in packs, or anything remotely useful on how to stop them. He's burning with the lack of anything else he can do. He needs to find somewhere he can summon Derek and remind him about that promise to bring him more books. He needs to get Scott to call out the werewolf pack again, tell them what they're really up against and find out exactly how many graves they've found desecrated. He needs to make Allison go through every last handbook and diary in all the hunters' library for anything that sounds even passingly relevant. He needs to know if they're rethinking their confidence that Derek is dead; needs to know Allison is ready to be the one to stand up and say _maybe it never was the incubus_ if they don't make the leap on their own.

He needs Scott to get back from running Lydia's messages to the hunters, who vanished into town an hour ago and are now holding everyone up. Any minute now, he's also going to need a much better excuse for wasting time pacing back and forth in front of the castle gates when he knows Lydia could and would find him something to do if she had any idea.

He really doesn't need to be ripped out of his thoughts by Jackson grabbing him by the arm out of the blue and slamming him against the nearest wall, but gets it anyway. "What the _hell_ , Jackson?"

"No, you tell _me_ what the hell," growls Jackson, leaning close enough to make Stiles go cross-eyed, "Two people – _dead –_ and there is no goddamn way you and your little werewolf friend are going to make me believe you don't know more about that than I do."

"Jesus, a little louder Jackson, I think someone on the other side of the castle might not have heard you!" Stiles protests in an urgent hiss, which Jackson pointedly declines to imitate.

"You _told_ us that incubus was dead!"

"It was! It _is_!" Which is a lie that Stiles cannot afford to have questioned by anyone in the household, let alone Jackson, which is most of the reason he follows it with a strategic bit of truth. "Not that it matters, because it wasn't an incubus that did this!"

"Wasn't it." A dozen layers of compacted sarcasm obscure any trace of a question in Jackson's tone.

"You think _Harris_ is incubus-bait?" Stiles hisses. "Incubi don't even kill like that! The hunters won't say anything because they don't want to admit they got it wrong."

Stiles abruptly has breathing room again while Jackson leans back to digest this. "So what _did_ kill them? If it wasn't an incubus, what?"

Stiles makes a rough estimate of the odds he has any hope of making Jackson understand the idea of a _volkodlak_ while the guy is literally breathing down his neck – and then, for good measure, the wisdom of trying at all, considering the real danger Jackson knowing what's out there will backfire on him and Scott in ways that lead to difficult questions from the hunters or another dead body or three. His gut doesn't find the odds encouraging. "Jackson, I am not having this conversation with you out here."

"Answer the question, Stilinski," Jackson growls, but over his shoulder, salvation has arrived.

"Scott! Just who I wanted to see!"

Jackson looks at Stiles like he'd just been asked to applaud the old detachable-thumb trick. "That's what you're going with?" He realises someone is actually behind him maybe half a second before Scott literally shoves him out of the way, apparently in too much of a rush to check his werewolf strength entirely.

"Stiles!" He looks distinctly bothered, and Stiles takes a second too long himself to realise it's not because he got back to find his best friend under assault by the village bully.

"Hey Buddy," says Stiles, then, "whoa!" as Scott throws a guilty look at the open gate and grabs him by the arm and tugs him urgently along the wall, far enough to stop a hushed whisper from carrying. "Hey, easy on the arm!"

"Stiles, the hunters are looking for non-humans at the fair!" Scott hisses at him.

Stiles feels what little is left in his stomach lurch downwards. "What? How?"

"They're making everyone still leaving drive through a circle of mountain ash!"

"But – Derek and the others, do they know?" You can walk into or out of that field from any number of directions, if you don't mind wading through a few brambles, but if you want to get a cart out of there, there's only the road, and blocking that off wouldn't pose any challenge for the hunters.

"I couldn't find them, but the wagon's still there!"

Oh, this is _not_ good. Derek and the others could've realised the trouble and snuck away, but an abandoned wagon won't go ignored, and Stiles would be amazed if the hunters couldn't find someone from around the village who remembers who owned it and can give a description. Derek and his little party make an impression. "What are you doing here? We've got to find them!" No, that's too slow, he can summon Derek. He can...

"Excuse me," says a voice, pitched to carry, from somewhere closer the castle gate.

It takes Stiles several seconds to recognise Boyd, and without Isaac and Erica trailing obviously along behind him, it probably would have taken much longer. It's not just the change of clothes – finer by far than the nondescript outfit he'd worn at the fair to blend in – Stiles would swear he seems _taller_ than he was yesterday. With a start, Stiles realises this is what _glamour_ looks like in action.

"We seek audience with the Lady Martin, if it suits her pleasure," says Boyd, in a voice Stiles' struggles to recognise at all. "The word around town is that you may have some job openings."

Scott and Stiles exchange the most horrified look of their lives.

* * *

The Lydia Stiles remembers from earlier that morning had emerged from her room a shade paler than her usual rosy glow, following through the motions expected of her with brief answers and clipped orders that did not invite question. The Lydia now meeting Erica, Isaac and Boyd takes not more than the space of few seconds to collect herself into a wholly different creature, ready to deal with her prospective servants with all the condescension of a true scion of the Martin line. Stiles can only watch and listen as Boyd becomes the second son of a merchant, well-educated and seeking honest work, as Lydia makes a show of inspecting each of them with a reserve that suggests she might ask to see their teeth at any moment. Far from turning them away at the door, Lydia has taken this as exactly the distraction they all so badly need.

Stiles is in the process of having some sort of revelation about how communication works between the gorgeous, privileged, and far too clever for their own good: from an exquisitely worded menu of half-truths and misleading statements, from behind a façade of polite fiction and forgery. None of them have paid the least attention to his frantic attempts to communicate the urgency with which he needs to drag them aside and explain to them exactly how this can only go very, very wrong.

"You put yourself forward for the position of steward, Mr Boyd?" For all that he's practically oozing glamour, Lydia looks him up and down with the air of a woman barely satisfied with what she sees. "You have some understanding, I would hope, of the labours required in the running of the household, of the management of the accounts, the protocols of book-keeping, and such other duties as the position would require?"

"I would not present myself thus otherwise," Boyd assures her.

"Hm. Then you're familiar, I would presume, with the extent and calculation of hearth and land tax required of a household of the stature of the Martins, and especially the particulars of shield-tax demanded of his nobles as set out under the reign of our late king?"

"Not intimately so," admits Boyd, "given I understood that to have been superseded in full by _scutage_ decree as laid out in the Statue of '24." Evidently, this is the right answer. Hysterically, Stiles finds himself wondering whether an encyclopaedic knowledge of tax law was ever among the traits traditionally ascribed to the fae.

"Very good." Lydia turns her attention to Erica. "And you?"

"Erica Reyes, my lady," says Erica, with what might be charitably described as a 'winning smile'. Unlike Boyd, her outfit is hardly finer (and barely more modest) than the one Stiles remembers from yesterday; Lydia's attention focuses rather on the elaborate plait of her hair.

"Tell me, did you style that braid yourself, Miss Reyes?"

Erica's smile widens, as she bobs through what is quite possibly the smuggest curtsy ever performed.

"Very nice," Lydia decides, and slides a flicker of attention on to Isaac. "And you are?"

"My own name is Isaac, at your service," Isaac replies.

"You understand we're only looking to fill the two positions."

"That may be a problem, My Lady, as Isaac is my only brother," fibs Erica, "and we've no intention to be separated."

"Hm." Lydia treats Isaac to a slightly longer once-over. "And what is it you do, Mr Reyes?"

"I can read and write or fetch and carry," purrs Isaac. "Whatever is my lady's pleasure."

"You know, we could possibly use another boy about the place," Lydia decides. "We might even afford it at a _slightly_ reduced wage."

Isaac gives an easy shrug. "As long as room and board is provided, I'm sure we can come to some agreement."

"I do think we might," agrees Lydia. Jackson stares at her in disbelief.

"Lydia, is this the time to be hiring?"

"Jackson," says Lydia, with infinite patience, "we are leaving in an hour, fate and fortune allowing. What other time do you imagine will present itself? Would _you_ like to take on Harris' duties? Rebecca's too?"

"You don't know anything about these people!" objects Jackson, clinging tight to what remnants of an argument he ever had.

"I'm sure we'll all get to know one another soon enough," says Lydia. "And if it proceeds they _aren't_ so well suited to their duties – we'll look elsewhere."

Nothing good ever comes from a situation where he and Jackson find themselves in agreement, Stiles has begun to realise. Unfortunately, nothing good ever comes from arguing with Lydia when she's made up her mind either.

The hunters are even less impressed with Lydia's impulse hire of her three new staff, small comfort though that is to Stiles, who doesn't even get to properly enjoy seeing Lydia put one over the Argents this time, no matter how obviously Lydia herself may be enjoying it. He and Scott spend the first leg of their hurried return journey doomed to a prolonged and awkward silence, painfully aware that if either of them start anything with Erica, Isaac or Boyd now, there is no way in hell it's going to stay at the conspiratorially low volume the open-air company requires.


	10. Chapter 10

It's almost sunset by the time the Martin household arrives at the inn for their first overnight stop. At their first free moment, Stiles and Scott discover an urgent need to go check on the horses, taking all three new hires along to 'show them the ropes'. Stiles is by then well past the point of caring how plausible his superiors might find the idea their new steward has anything he urgently needs to know on the subject of mundane animal husbandry. One more hour on the road, and dragging them all off into the nearest bush by the ear would have started to seem like a pretty good plan, witnesses be damned. They're having this out now, before he blows.

The stable door has wonky hinges and a latch that doesn't line up properly anymore, and it refuses to slam behind him in a satisfying manner once everyone's been herded inside. The odour of fresh horse manure adds very little to the gravity of the occasion.

"Alright," Stiles says, pleasantly, "Would someone like to tell me what in the hell you all think you're doing here?"

"Only what it looks like," says Boyd, with a casual shrug-and-smile evidently calculated to set Stiles' teeth on edge.

"It's called 'settling down'," says Isaac.

"Life on the road is all very well," adds Erica, "but we talked it over, and decided we all felt like a change."

"'Settling down'," echoes Stiles. "Okay. Uh-huh. Was this Derek's idea? Where is Derek, anyway?"

Erica arches an eyebrow. "Didn't he tell you? Derek's making his own arrangements. This wasn't his idea, Stiles. He doesn't even know we're doing it yet."

"Gave us a lovely speech this morning about how far we'd all come, and how sure he was we'd make it just fine as our own masters," Isaac throws in, casual as anything. "All very sweet – or it would've been, if he hadn't basically ditched us."

Stiles looks from Isaac to Boyd to Erica and back again. "Whatever happened to 'with lives like ours, it pays to stay on the move'?"

Isaac shrugs the sentiment away. "His words, not ours."

"What about all your stuff? Your wagon?" Scott asks them, latching onto a technicality like logistics are really what matters here. "You didn't just abandon it in the field, right? The hunters are bound to find it!"

"'Course not," snorts Boyd. "We _sold_ it."

"This morning?" asks Scott, apparently baffled by the idea of selling off one's whole livelihood on a whim.

"Wasn't hard to arrange," says Isaac. "What better place to sell a business than surrounded by merchants with new earnings to spend? Besides, Erica did the negotiating."

Erica grins at them broadly and flicks at a moneybag hanging from her hip. From anyone else, the gesture would have been merely drippingly smug; from Erica, it becomes borderline obscene. "Got quite the good deal for it too."

"Face it, opportunities like this don't come up every day," says Boyd. "Gotta be ready to leap on them when they do."

"'Opportunities'," echoes Stiles, in real disbelief. "So tell me, did Derek ever get around to mentioning the part where this tower you all want to live in is _crawling with hunters?_ And would you turn down the glamour already? You're going to start attracting moths, I swear!" Boyd declines to look particularly chastened.

"But it's also got _you_ , Stiles," wheedles Erica, like this is some sort of salient point. "You've done such good work covering for Derek and your werewolf-friend already... would it be so hard to cover for a few more?"

"And you'll do it," adds Isaac. "Because you know what happens if _we_ get caught..." Isaac leaves the implications of his trailing sentence to speak for themselves.

"Besides," says Erica, "what sort of friends would we be if we didn't stick around a while to make sure you're treating Derek properly?"

Threats and insinuations _already_? By all that is good and holy, Stiles does _not_ have to put up with this. "I woke up this morning and two of our staff were _dead_ – a man and a woman, if you weren't keeping track. And an incubus _and_ a succubus just happen to show up to take their jobs? You _can't_ not see how bad that looks."

"You know it wasn't us, just as well as we do," says Isaac, with a casual self-assurance that Stiles does not feel they've earned.

"The _hunters_ don't! They already think it was an incubus!"

"Come on, you're looking at this all the wrong way," says Boyd. "Wouldn't you like to have a few more allies in the tower? People who can help cover for you too?"

"We _have_ thought this through," Erica puts in.

"You have?" says Stiles. "Have you thought about how you're going to get through the _ring of mountain ash_ around the tower? I think the hunters are maybe going to notice if none of you can get into the building!"

Isaac shrugs, way too casual for Stiles' liking. "Lucky for us we've got you to let us in early," he says, while Erica produces a small vial filled with a dark-coloured fluid from somewhere and waves it at Stiles like it should mean something to him. "We'll take a shortcut. Be back before anyone knows we're gone."

"You do have a key to the tower, right Stiles?" asks Erica.

The realisation that that vial contains samples of _their blood_ , already drawn and ready for ritual ring-binding, keeps Stiles from entirely processing the 'key'-question so quickly as he might. "Are you... are you planning to _fly_ me there?" Could either of them carry that much weight and stay airborne? Is he about to hear some terrible plan to spread his weight between them, dangling from a piece of string? Is there a reason why Boyd has just pushed between them, interrupting the path of Stiles' eyes from one to the other and back again in a loop of unending incredulity?

No, wait – Boyd is trying to get his attention.

"Better than that," he promises. Stiles can find no evidence he's turned down the glamour at all.

* * *

Boyd's 'shortcut' requires a solid door with a lock on it, and getting access to _that_ requires everyone to sneak out again in the dead of the night and gather at the front room of the inn, a single lantern lending suitable atmosphere to the endeavour. Boyd stations himself by the door and holds out a hand. "Key?"

Stiles closes his hand around the key to the Tower, heavy in his pocket. He's had time to think about this, since they spoke earlier, though his conclusions were all but forgone by that stage. Under all their infuriating smugness, they do, unfortunately, have a point: Stiles has never had any real choice about granting Erica, Isaac and Boyd access to the Tower from the moment Lydia hired them. What matters now is that they don't have much more choice about hearing him out.

"If I'm going to do this," he declares, "you all have to promise me something. A binding geas. Same as what I made Derek promise me." He watches the three of them exchange glances before returning their attention to him, silently waiting for the details.

"You do no harm to anyone within the walls of the tower," says Stiles. "There is to be _no sex_ with anyone from the tower – none, okay? Whatever you need to do, you do elsewhere. And if the hunters _do_ catch you... you keep Scott a secret."

"Stiles?" The objection comes not from them, but from Scott.

Possibly giving him the heads up on those terms would've saved him this hitch. Stiles whirls on Scott, in no mood for argument. "If they go down, they're not taking you with them. I'm not negotiating on that."

"I'm guessing _Derek's_ terms didn't include the no-sex clause." _That_ objection comes from Isaac. Stiles whirls back again.

"Derek was negotiating from a different position. Terms are what they are. Take them or leave them."

"It doesn't work the same way on us fae," says Boyd. "I can make you that promise, but it won't bind me like it does them."

"Then you make that promise," decides Stiles, "and Erica and Isaac, you swear to me you're going to hold him to it."

Erica and Isaac throw uncertain looks at Boyd, who shrugs. "Fine by me." The other two exchange another glance.

"Alright," says Isaac. "We swear."

"Erica?" Stiles prompts.

"I swear," says Erica sweetly.

"If I'm caught," says Scott. "I'll promise you the same. It could happen," this last is addressed to Stiles. "No reason we all have to take each other down."

"Okay." Stiles pushes the key into Boyd's palm. "Take it away."

Boyd gives him one of those deliberately toothy grins Derek's cadre seem to be so fond of, and turns the key in the door lock. _How_ he does it Stiles doesn't entirely follow – he'd have sworn the lock on the inn door is at least a size too small for the key to fit at all – but the lock not only clicks, it swings open under Boyd's hand. The night air through the open door is a sudden, spine-chilling rush of cold – more than unseasonal, like winter itself breathed out through the opening gap. It takes Stiles several seconds of furious blinking to clear the mist out of his eyes.

When he opens them again the door is open; beyond, he can just make out the familiar, wide stone of the Tower steps sloping down into the forest below, illuminated in silver-grey in the light of the rising moon.

Stiles takes a deep breath. So. This is happening.

"I'm going too," says Scott. "Empty tower, middle of the night. We _know_ there's something out there hunting us – safer this way."

Stiles sends Scott a silent, fervent _thank you_ , both for the moral support and for Scott's having had the goodness to make it sound like a sensible precaution rather than a meagre hand-holding exercise. It's beginning to dawn on him just how much he's missed having Scott in his corner through all the months he's kept Derek secret. The idea of having to face the incursion of Derek's demon pals into his home without that back up doesn't bear thinking about. "Well, come on then, let's get this over with."

There's another rush of inexplicable cold as he sets foot through the doorway, but Stiles would probably have been disappointed if there wasn't _something_ to mark the occasion. The stone on the other side is reassuringly solid under his feet.

"Don't be too long," Boyd warns them, from over the threshold.

"How long is too long?" asks Stiles.

"Just don't be too long," repeats Boyd, unhelpfully.

Stiles pettily wonders whether Deaton has any relatives among the fae, and whether this might explain a thing or two about his attitude. Grabbing Scott by the sleeve, Stiles drags him along – mostly in awkward backwards hops while Scott stares back at the Tower rising above their magic doorway with naked fascination. It's been long enough since Stiles renewed the ash line that he has to concentrate to find it again in the dark, but the steps involved in breaking-and-reforming with mixed ash and blood have begun to feel almost routine.

By the time he's done, Scott's mostly given up making sense of the Tower, and is making a face. A thinking kind of face. "What?" Stiles asks him.

Scott shrugs, apologetic. "Maybe... this won't be so bad? Having other people we can talk to around, I mean. Isaac seems kind of okay, when you can get him to stop posturing, and..."

Stiles isn't touching that statement with anything friendlier than the end of a very long stick. He's not done being mad at them, and it's not fair for Scott to start making gestures this soon, when they've yet to do anything more deserving than be irritatingly smug about their own cleverness. "Have you thought about what you're going to tell Allison yet? Remember how much fun keeping the wolf thing from her used to be?"

The look on Scott's face suggests he's been trying not to. "She... wouldn't _want_ to know, right? It'd only make it worse for her, having to keep more secrets from the hunters."

Stiles thumps him on the back. "Sure, if that's what you wanna tell yourself," he says, but mostly because he doesn't have a better answer.

They're halfway back to the door when Scott says, "Hey, did Derek ever say anything about someone called Laura to you?"

Stiles stops dead. "Laura? Why?"

"It was something Isaac said the other night – thought I should bring it up before I forgot. I think... she was someone they used to know? Erica gave him this look and they changed the subject right after."

Stiles wracks his brain, but he's pretty sure that's a name he's never heard from anyone. "Did it sound important?"

Scott gives him a hopeless look, and jogs the rest of the way back to the door. Boyd locks it smartly behind them.

* * *

By day two of the trip Stiles has more or less resolved to bury the worst of his misgivings in a shallow grave and give the demon-pups-three at least the one chance to prove this doesn't have to go as badly as he fears. His new well of patience lasts for all of a dozen hours before they pull into their second inn for the night, whereat the innkeeper's daughter swiftly takes a shine to Isaac (certainly not without a fair share of tacit encouragement on his part) and is later seen leaving the common room to "show him ( _and Erica_ )to their room," at a suspiciously early hour. Stiles has little doubt there's any enthralling going on, but nothing about their little tryst is in any way subtle. The mystery is hardly improved when both of Lydia's newest employees reappear an hour later, sans the innkeeper's daughter – who is, in Erica's words, "Taking an early night."

Possibly – just possibly – if they hadn't both had to look so damn _pleased_ with themselves, Stiles could've let it slide. This is the last night they'll be officially spending outside the Tower for what could be weeks, and if Erica and Isaac have taken it as their last chance before the drought – well, Stiles only has his own rules to blame. Realistically, it's no bad thing for them to get this over with early – and right under the hunters' noses at that – because everyone will get to see the innkeeper's daughter alive and well tomorrow morning, and that could head off a number of nasty suspicions before they have the chance to form at all. But if Erica and Isaac actually want people to buy the devoted-brother-and-sister act that got them their new jobs, then this – this is emphatically _not_ the way to go about it.

And god, do they have to look quite so smug? Is this their idea of keeping their sexual conquests _subtle_? Doesn't all that _guess what-and_ / _or-who I was doing last night_ bullshit ever get _old_ , when you're at it fifty-two weeks a year? They're freaking _sex demons_ for crying out loud! That's gotta be like if Stiles took time to preen over being able to spell his own name.

Lydia, meanwhile, has been largely monopolising Boyd's attention, engaging him on topics from local history to obscure Latin proverbs – in what might charitably be called an earnest effort to assess the breadth of his learning, but which, realistically, is more likely a string of calculated attempts to trip him up. All hope that Boyd would know better than to rise to the bait, running himself the risk of letting a little _too much_ slip with every careless answer, fades from Stiles' estimation very quickly. Boyd, being a literal freaking pixie raised by demons, cannot resist the chance to show off, which is a lovely way to build his reputation, but not so great for subtlety. Stiles can do nothing but listen while Boyd chatters on, like Lydia's blatantly strategic attempts to trip him up _really are_ no more than a bit of fun, and like the inevitable verbal slip-ups which reveal the dazzling elven stranger in every faerie story Stiles has ever read are something that _only happen_ in stories, rather than equally transparent cautionary tale for the education of both species.

Scott spends the final day of the journey frowning a lot and trying, with typical McCall awkwardness, to change the subject or inject himself between Stiles and the other three whenever possible. Stiles spends it seething like a pot on the boil.

When they do finally make it home, he makes all of a ten minute token effort to help with the unloading before he instructs Scott in no uncertain terms to cover for him and stalks off into the woods. He doesn't care anymore that every non-human in the Tower could guess exactly where he's going; he needs to get this out of his system before something explodes.

He stops only once he's gone far enough from the Tower that a raised voice shouldn't carry, and _wants_ , in the deliberate way he's learned will get results. Hardly five minutes have gone by before Derek lands before him, a look on his face that suggests he's caught the theme of Stiles' interest in seeing him fairly clearly.

"How bad?" he asks without preamble.

"How _bad_?" echoes Stiles. "Harris and Rebecca had the life sucked out of them three days ago, and your little _coven_ ambushed Lydia at the castle and smarmed their way into taking their jobs. How bad would _you_ call that?"

The look that near-comical disbelief that settles onto Derek's face quickly becomes one of the more viciously vindicating experiences in Stiles' recent memory. "At least now I know they weren't lying when they said it wasn't your idea."

"I'm going to wring all their necks," Derek growls. "Of all the _stupid_ goddamn stunts -"

"Yeah, save me a seat when you do," snaps Stiles, "because those three? Not my favourite people right now."

The rage in Derek's posture stutters, and melts halfway into concern. "Stiles, you don't think they were the ones to-"

"Do the killing? Well _I_ don't – not that you'd get to blame me if I was having some _doubts_ about that right now," That part hits hard enough to make Derek actually flinch, and Stiles is feeling just petty enough to get a nasty sort of satisfaction from the point, " – but the hunters are going to find it _really convenient_ if they catch wind there's a new incubus and succubus in town. You didn't _see_ how they watched your pals crossing the mountain ash line, okay, they're suspicious already!"

"They made it across?" asks Derek, honing in on what is actually the more pressing issue in Stiles' rant with infuriating accuracy.

" _Yes_ , I got them through. Boyd did a thing, it was complicated. Beside the point now."

"They're inside the Tower?"

"Yes! You've got to _do_ something!" Stiles begs.

Derek sighs, short and angry. "Stiles, I did not mean to bring this upon you," he pronounces, labouring every word, "and I am _sorry_ ," this comes out through his teeth, evidently no easy admission, "for my part in this, but what exactly do you expect me to do?"

Stiles hesitates. "Look, I'm not saying _literally_ wring their necks, just make them get out of here!"

Derek just shakes his head. "They can't leave now. Not this soon, it would look even worse. And I couldn't order them to leave anyway. Not anymore. I don't have that kind of authority over them." The grudging tone of Derek's voice speaks of a history that goes a long way down, but Stiles isn't feeling terribly mollified.

"Can't you at least _try_? You may not be their elder, or alpha, or whatever you call it, but they still-"

"Whatever I say to them now, they'll know it came from you," Derek counters. "And that would only make them more determined to stay. I can't help you with this. I'm sorry, Stiles." Derek takes a deep breath. He looks defeated. "Please – do what you can to take care of them."

Stiles feels himself deflate. Derek doesn't ask him favours – makes demands, sure, suggestions occasionally, but this is new, and weirdly disarming. This is Derek _caring_.

"You know I will," Stiles promises, meaning it more than he'd realised he was going to.

Derek nods his head, absent and resigned. "What about the dead? Was it the same as the last time?"

"Yeah," Stiles agrees, without enthusiasm. "I looked it up – apparently the plural of _volkodlak_ is _volkodlaki_. There's a neat little word I never wanted to have to know."

"Did anyo-" Derek begins, and stops, because all of a sudden there's an arrow buried in his chest. There's an arrow shaft protruding from his actual flesh, and Stiles doesn't even remember hearing the bowstring. He and Derek stare at it with matching looks of incredulity for the space of a moment before Derek seems to properly catch up. He falls to his knees with a roar.

Stiles has wasted several more seconds in mute, stupid horror before he gets to remembering that arrows don't just fall out of the sky, and that he has maybe seconds to figure out wherethis one came from before everything gets much worse. The crunch of a hunter's heavy boots in the undergrowth has him jumping halfway out of his own skin.

"Stiles, get away from there," calls the hunter.

Stiles knows that voice, his heart simultaneously leaps and drops at the recognition. His own personal nightmares have never yet featured he image of Allison Argent emerging from the woods, eyes hard and crossbow loaded – but Scott, being Scott, has described the experience in such vivid detail that the reality gives Stiles a soul-shaking rush of deja-vu. Of all the hunters who could have followed him out here, Allison represents either the best or the worst of so many bad options. That the crossbow is pointed at Derek rather than him doesn't really help.

Stiles does the only thing he realistically can: he puts himself between Derek and the danger. "No!" Dramatic acts of spontaneous bravery are so verynot his thing, but by the time he remembers that he's already there, holding his hands up in a gesture of peace, though he's not above doing his best to cower behind them at the same time. "I know this looks really bad, but please, give me just one chance to explain."

Allison narrows her eyes slightly. She doesn't look terribly convinced.

"Stiles, _go_!" Derek growls. "I'll heal! Just get out of here!" A scuffing noise from over Stiles' shoulder is probably Derek trying to get back to his feet, but another snarl of agony is all that comes of it. What the hell was _on_ that arrow?

_Going_ is not an option. Stiles thinks quickly. "Derek," he says carefully, "this is Allison, I don't think you've met. Allison, Derek. We go way back, me and Allison, and I'm pretty sure she's not actually going to shoot me."

"Not if you don't make me," says Allison, who is really far too calm about this – or at least faking it with a verisimilitude Stiles finds disturbing. "Stiles, this is going to be much easier for everyone if you move away from the demon."

"So you can make sure the next arrow hits him in the _head_?"

The tight line of Allison's mouth is probably a 'yes'.

"Allison, I know how this has to look, but it's not, I mean it, I-"

"Why don't you tell me what you think this looks like?" suggests Allison, before Stiles can figure out precisely where he's going with that plea. He's got her talking. That's good. He can work with that, crossbow or no. Probably. "I'm not enthralled, I promise – and I know that's just what someone who was in the thrall of a demon would probably say... and maybe they'd say that part too, but if there was any way I could prove it to you..." This all sounded much better in his head.

Allison rolls her eyes. "Stiles, I know you're not in his thrall."

"You _do_?"

"You can't keep someone enthralled for more than seven days without killing them, and we both know he's been around here longer than that," Allison explains reasonably.

"I... knew that." Stiles did, honestly. It's just hearing Allison bring it up like an actual point in his defence that's throwing him. "I promise you Derek isn't a threat to anyone. God, I just got through explaining all this to Scott – he'll vouch for me, and for Derek – I mean, he doesn't even _like_ Derek, but..."

" _Scott_ knows about this?" That part startles Allison enough that her aim falters, but the bad news is that it's faltered in the direction of Stiles' chest.

" _If you lay one hand on him I will tear your flesh from your bones before I let you die!_ "

The outburst from Derek is so sudden and unexpected that it leaves Stiles uncharacteristically short on a response. From Allison's end, however, both the crossbow and her jaw drop in synch.

"It's not Lydia," she says slowly, "it's him, isn't it? It's been him all along."

The question makes so little sense to Stiles that he's not sure at first who she's talking to. It's Derek she's looking at, but then again, she's been looking at him all along, even when she was talking to Stiles. Derek stares back, defiant, but only holds her gaze a moment before looking away.

Allison seems to shake herself and re-emerge somewhat from whatever scary hunter-survival mode she's been operating under until now, though she doesn't put the crossbow down. "Stiles," she says, sounding altogether more like the Allison he knows, "you and I really need to talk."

Stiles breathes a sigh of relief. "Talking I can do."

"As for you," Allison turns her attention back to Derek. "Will you swear to do me no harm if I let you live?"

Derek seems to consider his options, but he rumbles out an, "I swear," without additional encouragement from Stiles. If he had to guess, Stiles would say the rumble wasn't even reluctance, just ordinary pain in progress – and, god, he can help with that, what is he even doing?

Stiles hurries over and puts a hand on Derek's shoulder. "Does that help? Feeling what I'm feeling, not what you're feeling, right?"

"Yes." From the look of things, Derek is still feeling rather more of what he's feeling than he'd like to be, but he seems better immediately. "Thank you."

"The arrow isn't barbed," says Allison, approaching Derek now without fear. "It should come out cleanly."

It takes a second for it to register with Stiles that Allison isn't coming over to do the first aid exercise herself (which is probably a little much to ask, even if she does trust Derek to keep his word), and that Derek, much as he's trying to act tough, doesn't look in any state to do it himself. "Me?"

Derek flicks one last, distrustful look at Allison, then nods at him. Stiles swallows, and gingerly wraps his fingers around the shaft sticking out of Derek's body, the wound leaking a sickly, black trickle down his chest. Derek shudders and closes his eyes.

It takes two tries for Stiles to get the thing all the way out, in a minute-long spell of horror that he hopes never to have to revisit again. Thank god incubi heal quickly; Stiles has seen enough of Derek's blood to last him a very long time.

"What did you use?" Derek growls. He's looking at Allison, who swallows and replies.

"It's a recipe from my father's textbooks. The effect should lessen once you start to heal. The rest should work its way out of your system within an hour. It's not a long-lasting poison; it's only meant to heighten pain."

Stiles is used to the hunters lacing their arrows with wolfsbane, but this is cruel and unusual even by their standards. "Were they going to use that on _Scott_?"

"It's not for werewolves," Allison tells him, like this should have been obvious. "Specially made for demons."

_Because an incubus' greatest weakness is extreme pain_ , Stiles' memory fills out helpfully – it's not so long since Derek admitted to him this was exactly what his kind _didn't_ want their enemies knowing. A niggling fear that Allison – and by extension, the rest of the hunters – know more about what's going on here than he does has been growing in Stiles' gut for some minutes now, and it feels just about ready to ripen.

"I think you'd better go," Allison says to Derek.

"And leave him with you?" says Derek, jerking his chin at Stiles.

Allison hefts her crossbow. "You can leave now, or I can hold this crossbow to Stiles' head until you do."

Stiles senses this is not going to be resolved without his input. "Go on, go. You'll know if I need you again. I'll call you later, I promise. If I'm dead then, well..." Possibly specifying exactly what Derek should do to the hunters if it comes to that would not be terribly diplomatic.

Derek gives Allison one last, long glare, before turning on his heel and taking to the air.

Stiles watches him go with what might be relief, but doesn't quite feel ready to commit itself that far. It's as if he's already felt everything worth feeling about this today, and he's run out of emotional responses that apply. No matter how little he's going to enjoy this conversation, what he told Derek still holds: it's only Allison, officially the last person in the Tower with any right to judge him for sleeping with an allegedly-dangerous supernatural creature. Stiles can handle Allison – though his confidence on that front isn't resting at an all time peak. The reminder in this whole debacle that Allison is still ahunter, whatever else she may be, has left a bad taste in his mouth.

He sits down heavily on a fallen log and rubs absently over his hair as he considers where to begin. The rough bark digs uncomfortably through the fabric of his pants, like something that would probably make some sort of great metaphor for something if he had half a damn left to give. "So, I guess I better start by saying that I'm pretty sure Derek is the kind of incubus that doesn't kill people. Or at least, he said he doesn't, and I haven't found a hole in his story yet – and I've tried, trust me."

Allison nods, which could just as well mean _I do_ as it could _I'm listening_. "Stiles," she says, stepping closer, "I'm going to need you to start from the beginning. How long this has been going on?"

"Ever since the night Lydia was attacked. I didn't kill the incubus that did that, _Derek_ did, then he climbed into the room to make sure I wasn't going to tell anyone he was there. For other reasons too, but – you get the idea."

Allison's eyebrows twitch downwards; whatever version of events she was expecting, it doesn't seem like this was it. " _You_ summoned him?"

"What? No! I wouldn't know how, I swear! Derek – Derek said he was tracking the other incubus – it was, I don't know, some sort of vagrant that moved in and started killing. Derek and... he just kind of gets by by keeping quiet and staying out of sight. Said he had to put that other incubus down before it got so much attention it started a witch-hunt. We'd all have been dead that night if he hadn't caught up when he did."

Allison seems to digest this. "You told us you helped my father track and kill an incubus, only a week ago," she says, the question implicit.

"I helped Derek fake his death to throw the hunters off his trail," Stiles admits. "But he didn't kill any of those people, Allison, I swear! Me and Scott didn't imagine the volkodlak! It was – _really_ real."

"I believe you." Allison sounds like she does, more's the wonder. "But if you didn't summon... Derek, if there isn't a geas binding him, I don't think I understand why he's still here."

"I don't think _I_ understand why he's still around sometimes," Stiles admits, surprising himself with the honesty. "He just kept coming back until I got used to it."

Allison doesn't entirely seem to appreciate his honesty; her earlier confusion is settling into something quite uncomfortable. "Stiles, I'm not sure you understand what you've got yourself into. If my father or my aunt find out about this, it's not just Derek they're going to be looking for."

"I know." Stiles sighs. "I'm helping him, I'm probably still in his thrall – as far as they're concerned, time limits be damned. I'm gonna be culpable for anything he does. I get it-"

"No, I don't think you do." Allison takes a deep breath. "There are certain things my family knows about the incubi that we don't share with anyone. Things we don't put in our manuals – not even in _code_ – that we only pass on by word of mouth, to a full-fledged hunter who's come of age. Things we're sworn never to share with _anyone_. I need you to understand what it means if I tell you."

Stiles feels his stomach sink somewhere into the region around his knees. Even his natural curiosity struggles to gather a healthy interest. "What... kind of things?"

"We know they don't always kill," says Allison. "They don't needto drain the life out of their victims, and some of them don't. Nothing Derek's doing with you is unheard of."

"That's not so-"

"There's more," Allison cuts in before he can say more. "We know they can only hold you in thrall for a matter of days, or until their desire has been consummated, and if they _do_ , they leave that human immune to their influence."

None of this is exactly news to Stiles, but the day a hunter _confirmed_ Derek's story was one he'd never expected to see. "You _know_ all that?Why wouldn't you _tell_ people?"

"Because it's the ones that _don't_ kill that we're most afraid of," Allison explains. Her voice has been steadily dropping since she started on this subject; it's down to barely more than a whisper now. "Sometimes in the past, a human who survived the encounter has found a way to turn the thrall back on the demon. To bind it permanently to a witch or wizard's will."

Stiles is starting to feel completely at sea. He's never even _seen_ the sea. "Wouldn't that be a good thing?"

"Did you ever hear of the demon of Lyonesse? The slave- _djinni_ of the kingdom of Solomon? Those were _incubi_ and _succubi_ , every last one." Allison hisses the words, even knowing there's no-one else around to hear. "Normally demons aren't interested in human affairs: they only kill to feed. But with a human pulling their strings, everything changes. Each one has the strength of a dozen men, can heal from almost any injury and can kill or enslave with a touch; can come in the night and leave without ever being seen. Can you imagine what can happen if that kind of power falls into the wrong hands?"

Stiles gapes at her and does his best not to imagine anything of the sort. "How is that even possible?"

"We don't know! Some versions hold that it's some kind of deal, maybe the demon exchanges years of service for a human soul. Or maybe the human sets some sort of trap or counter-spell. All we know for sure is that it happens _after_ the desire the demon inspires has been consummated and the thrall no longer holds. After, the demon no longer needs to seek out other victims. The bond with its master is enough."

Realisation settles on Stiles like a physical weight. "That's what they think I'm doing with Derek? I've got _him_ enthralled?"

"They don't think it's you, Stiles. They think it's _Lydia_ ," hisses Allison.

"Lydia?!" Stiles has officially lost this conversation. "But she was the first one attacked!"

"Which is what _usually happens_ when a summon-and-bind attempt goes wrong!" insists Allison. "It looks _bad_ , Stiles! That 'vagrant' incubus didn't leave any other human victims; the hunters' network has _looked_. No-one found so much as a rumour of a single suspicious death anywhere on this side of the country! Incubi don't fly that distance for nothing; they don't make spectacles of themselves without a reason. This would all look _very bad_ for Lydia even without her mother's legacy hanging over her!"

Stiles can practically feel his world shifting on its axis under his feet. "Her moth... the _hunters_ think she was a witch too?"

"They don't _think_ , we _know_." Allison certainly doesn't sound like someone suffering from the least amount of reasonable doubt.

"But... she was set up!" Stiles tries, possibly more by habit at this point. "No-one ever found any real evidence even after they tore her room apart!"

"No-one found any of her _equipment_ or her _texts_ ," Allison corrects him. "That means she could have left them behind for Lydia to find!"

"But Lydia wouldn't... Allison, you _know_ Lydia! This is nuts!"

"What's _nuts_ is _two_ incubi appearing where there've been none for a century, on the doorstep of a young lady whose mother was accused of witchcraft, but escaped before she could ever stand trial! She was accused of consorting with demons, Stiles. That's a very specific charge."

"Oh my god." Stiles suddenly needs to sit down. The problem is he already is sitting down, and it doesn't seem to help. "Does Lydia know about all this?"

"I think that's pretty likely, don't you?" says Allison.

"Did _you_ think it was her?" It does Stiles no good at all to realise that the reason this conversation is giving him déjà vu is because he's remembering Kate messing with Jackson, only it's starting to look less like Kate messing with her ex for fun, and more like a hunterplanting very specific suspicions in the mind of someone close enough to Lydia to give them the lead they need. It does no good to remember now that he has a few reasons of his own to suspect Lydia knows more about demonology than she lets on in public.

"I don't know what to think anymore," Allison tells him, tersely. "Lydia's my friend, but people are dying, and as an Argent, it is my sworn duty to find who or whatever is responsible, whatever it takes. My family has good reason to be careful who they trust. We both know she's smart enough not to get caught that easily."

_She's smart enough not to get involved in something this stupid_ , thinks Stiles, furious in Lydia's defence. "Well, now you know: Derek's not here because Lydia summoned him, or because she bound him to anything, he's here for _me_. Lydia's not involved. And I haven't _bound_ him to anything either!"

Allison folds her arms. "Are you sure?"

"You think it's something I could do by accident? He sure doesn't _act_ enthralled. I can't even make him answer simple questions, and that's not even getting started on his attitude! He put _me_ under a geas of silence!"

Allison frowns at him.

"Well not anymore, obviously, he let me break it, but he still did that – on his own, without me even asking. There is _no_ commanding going on!"

"What _is_ going on?" asks Allison, carefully.

"What's going on is that Derek crawls in through my window once or twice a week and we do things I have no desire to spell out for you. If we're feeling really romantic he insults my intelligence and I remind him about that time he tried to get it on with your aunt. I don't even _know_ what we're doing, he won't talk about it!"

Allison takes another deep breath. "Look, Stiles, I don't pretend to understand what's going on here, but you need to figure it out before someone else does." She straightens and looks over her shoulder. "And we both need to get back to the Tower before someone else comes looking for us. Coming?" She sets off without waiting for him to follow.

She's out of sight altogether long before Stiles stumbles his own way back to the Tower, mind buzzing like an angry hive.

* * *

Stiles spends the rest of the evening with his thoughts in chaos. Scott eventually pins him down and tries to talk to him about the situation with Erica, Isaac and Boyd, but by that stage Stiles is quite unable to say for sure if he's actually seen them since getting back to the Tower, and doesn't have much to contribute. Even once he's finally dismissed from his duties it's beyond him to do much more than lie on his bed staring at the ceiling for what feels like hours, turning it all over and over in his head in an endless, useless loop.

The idea he's got Derek under some kind of spell is... is just... Stiles does not have words for how completely insane the idea is. It's crazy. It's beyond nuts. It's like what you'd get if you took all of Stiles' earliest insecurities about their relationship, shook them up and tipped them out upside-down. Like if someone had tried to tell him the first incubus showed up for _him_ , not Lydia. Like saying demon-blood on a dagger would have pointed to _Stiles_ ,not Derek. Like what he might get if he ripped up his whole bestiary and glued the pages back together at random, so that imps in your parlour became a common sign of glamour and burning a werewolf at the stake part of the ritual to generate mountain ash. Stiles isn't ready to begin to reassess his life on anything like the level it would take to make this true, so it's a good thing it's far too crazy to have any sort of bearing on reality.

Unfortunately, parts of his brain haven't quite got the message, because they're busy reassessing everything, and that includes remembering Derek's exact wording from the time when he'd said, _it's been a long time since this was something I could walk away from_. He's remembering Erica's comment about sticking around to make sure he 'took good care of Derek.' He's remembering that thing Derek said only hours ago, _if they knew it came from you, they'd only be all the more determined to stay_.

Stiles knows what demonic magic looks like – pentagrams and chanting, a bloody dagger swinging on a line. You can't do something like that by accident.

You can't bind a demon to you just by thinking really hard once in a while about how much you'd enjoy some more sex.

He doesn't hear Derek come in. Derek doesn't bother to say hello.

"I thought we were past this," Derek says instead. He doesn't sound happy about having been wrong. Stiles rolls over and has a go at _wanting_ this damn relationship to get simpler already really hard, just to see if he can make Derek flinch.

Aloud, he says, "What, you coming through the window with a frown and a cryptic remark? Or me having to re-examine what the hell I think I'm doing here every time I learn something new?"

"The hunter." Derek is apparently thinking aloud. "What did she tell you?"

"Why? Weren't you listening? You can't read that from me, just because I..." Stiles makes himself stop, scrubs both hands through his hair. They've had this argument; they've had it a dozen times over in minor variations, and it never gets them anywhere. This is not the argument he needs to have with Derek today. "Derek, did I... are you _bound_ to me? Is that what's keeping you here?"

Something in Derek's face shuts down. He takes a sharp breath. "How much did she tell you? Did she know how the binding works?"

"You are. Oh my god, that was a yes. That was you telling me I bound a demon to me and-"

"Stiles, this is important," says Derek, interrupting Stiles' epiphany. "Did she know _how_ one of us becomes bound to one of you?"

"She said it was some kind of ritual. I haven't done any rituals!" Stiles glares at Derek, daring him to contradict this. "Okay, we made a couple of deals and I let you through the ring, but it _can't_ be that simple!"

Derek breathes out, and some small part of the tension in his shoulders bleeds out with it. "No," he says, "it's even simpler than that. There's no ritual. They assume there must be, and we let them."

"Then how?" says Stiles, pushing off the bed. Derek's barely taller, from his feet Stiles can look him right in the eye. "We haven't _done_ anything! Except fuck, and that-"

"And every time we do," says Derek, every word deliberate, controlled, "I feel what you feel – every need, every desire – a little more strongly, until it overwhelms my entire being." He stops there, gives this revelation some time to sink in. "You thought it would be more than that? You're wrong. That's all it takes."

Stiles feels numb. "What?"

"Do you need to hear it again, or do we need smaller words?" Derek actually drops to his _knees_ , right there on the floor, like he seriously thinks that act of supplication is what Stiles' needs to understand. "I. Am bound. To you." Stiles takes an instinctive step back; he's starting to regret standing up at all. "Anything you want, I feel. Anything you will, you could have me do. Every time we touch cements that. I'm yours, Stiles. I've been yours all along."

There's a tiny, traitorous part of Stiles that _sings_ at hearing, _I've been yours all along_ from Derek's lips. The rest of him feels sick. "Derek, since when do you do whatever _I_ want?"

"Just because you've never pressed that advantage yet doesn't mean it's not there," Derek counters, looking away.

"I can't even make you answer my questions!"

"Because _I can't give you_ the answers you _want_ without lying to you!"

"Why didn't you tell me?" The question hasn't left his lips before he's realising how stupid it is. He wouldn't have wanted to know. He wouldn't have believed it even if Derek had told him. He deserves every bit of the incredulity on Derek's face right now.

"Tell you what, that you could make me your slave?" Back on his feet, he advances until he has Stiles crowded against the wall. "You could make me do anything you wanted? Kill for you, die for you, kneel at your feet? Seduce or enthral any enemy you named? Call Isaac or Erica or Boyd up here and tear them apart while you watched?"

"Stop," Stiles whispers. The worst part might be that Derek does – he steps back and away, and that's the only reason Stiles can find the air to ask, "You _knew_ this was going to happen? From the start? Why did you let me?"

"You think I planned this? Any of it?" says Derek, eyebrows reaching new heights. "Tracking that rogue to a tower full of hunters? You think I _knew_ that woman in the woods was only letting me get close to stab me? That I'd have to come back here to explain your geas to you in smaller words?"

"I had no idea I was doing it!" Stiles pleads.

"No. If you _had,_ " allows Derek, his voice falling with every word,"it would have been that much easier to turn you down."

It might be the first really honest, fair thing he's said since he came in. Stiles finds he can't meet Derek's eye, can't hardly make himself look at him at all. "I think you should probably go," he says, to a far wall. He's going to cry, and he doesn't think he could bear to do it in front of Derek. Not right now.

Maybe he'd expected Derek to challenge that, he doesn't really know. There's definitely a moment where Derek hesitates, but then there are footsteps, and the sound of wings beyond the window as he disappears.


	11. Chapter 11

Stiles does cry after, though without much stamina or commitment. A handful of angry tears are about all he finds he has the stomach for, and they don't help much either. At some point not too much later that night he must have fallen asleep, because the next thing he clearly remembers involves waking up to the discovery that daylight is sneaking in through the window, and daylight of a quality that means he's badly overslept. A crick all down the back of his neck suggests he must have zonked out where he sat and not moved once all night.

It occurs to Stiles that the last thing he wants to have to do this morning is deal with other people. Unfortunately, in this job, dealing with people is virtually unavoidable, and the least appealing way he could go about failing to avoid said people today would be to sit where he is until someone else comes down to find out what's wrong with him. This proves very barely sufficient motivation to get Stiles out of bed, already rehearsing _I didn't sleep well and I don't want to talk about it_ , in between the equally pressing mental demands of internally cursing the cold of the Tower's stone floors, and the rest of the universe just on principle.

The door to the hallway swings inwards under his hand to reveal Isaac, holding a tray containing half a loaf and a mug of water. "You missed breakfast," he says, helpfully.

Stiles stares balefully at Isaac's offering and tries to determine whether the more appropriate response would be the simple _thanks_ , or whether this is the moment to make something of the fact Isaac was almost certainly waiting there to spring this on him. He opens his mouth with the general expectation that whatever falls out of it can't make the day ahead of him any worse.

The sudden appearance of Erica behind Isaac and his tray cuts Stiles off before he can find out what that would have been. "Bad night?" she greets him, pushing past the both of them to get into the room. "I'd ask what Derek did to keep you up, but why don't we just skip the part where we all pretend not to know?"

"To clarify for my associate," says Boyd, joining Isaac in the doorway, "she does mean the argument, not whatever you and Derek get up to normally."

Stiles' mouth feels suddenly very dry. He doesn't care how late he may have overslept, it is officially far too early for his day to have begun finding whole new horrors to spring upon him. "You were _listening_?"

"Hard not to," says Isaac, with a shrug.

"You were _all_ listening?"

"Not me," says Boyd. "But they gave me a summary. Demon business – I'm just here for moral support."

"Was _Scott_ listening?" Stiles is a thousand years from ready for Scott to know any of what he and Derek talked about last night. He's barely started on regretting having told Scott about Derek at all.

"I wouldn't worry about Scott," says Isaac, looking thoughtful. "It's a demon thing, mostly, that made it so hard to ignore. If Scott heard, he'd have beaten us down here."

Stiles makes a half-hearted attempt at feeling grateful for small mercies, but gives it up as a losing battle. "How.... _much_ did you hear?"

"Enough," croons Erica. "So, _Stiles_. How does it feel to know you've got a real, live demon at your beck and-"

" _Don't_ ," Stiles snaps. "Just don't, okay? I didn't ask for this. And I really _don't_ need to talk to anyone else about it." What Stiles needs is a solid distraction, and all of them _out_. He yanks the tray out of Isaac's hands and sets himself at the bread as though it deserves his full attention. "Thanks for breakfast, goodbye."

In the ensuing silence, Stiles would swear he can practically hear them all exchanging glances behind him. Someone shuts the door, but the lack of departing footsteps preceding it doesn't bode well. Stiles attacks his food with his fingers and teeth and wishes them all away.

"Considering the job Derek did of explaining things," says Isaac, slowly, "actually, I think maybe you do."

Stiles swallows uncomfortably and drops what remains of the loaf back on the tray. "What'd he miss? The warning about what you'll all do to me if I take advantage?"

"We didn't come here to threaten you, Stiles," says Erica, in a tone uncharacteristically close to what might be 'comforting' coming from anyone else, and Stiles finds he has something in his eye again, for absolutely no good reason. "Bit meaningless after what we all swore to you back at the inn, isn't it? 'Least as long as you stay in the Tower, and I don't see that becoming a problem."

With everything else he's had on his mind, Stiles hadn't really got up to thinking much about what the three of them must logically think about him and Derek. The fact they'd accepted his terms as a geas _despite_ the implications Erica has just so kindly outlined is more than had occurred to him, and it all seems like it might mean something Stiles isn't quite ready for.

"Of course, if _you_ were planning on threatening us," adds Isaac, like he's only talking about the weather,"it's not as though we could say the same. And after Derek's speech last night, you can't not know that's an option. If you still want us out of here, there isn't much we could do to stop it."

" _Jesus_ ," Stiles breathes. How in all the world do they have the gall to make a _joke_ out of this?

"We should be the ones asking if we have anything to fear from you," says Erica. "Do we?"

"God, no." The answer's out before Stiles has even thought about it, and he wants to go further – to ask _how could you even say that?_ But there's an answer to that, and they'll give it to him if he gives them the excuse. For a moment Stiles furiously hates them all for twisting this so he can't even want them out of his life anymore without hating himself for it, not even if he woke up feeling like he never wants to have to hear the word _demon_ again.

He needs to steer the conversation somewhere else. Anywhere else. "You all knew what was going on with me and Derek all along?" Having guessed the answer doesn't mean he doesn't still need to hear it out loud.

"Well, yeah," says Isaac. "'Don't go back for seconds' is about the first golden rule he and... well, he ever taught us." He shrugs. "Derek always was the 'do as I say, not as I do' kind of mentor."

Stiles has no great difficulty believing that. "You have sex with the same person twice – is that really all it takes?" Derek's explanation was a little hazy on this point. Possibly this is the wrong detail to fixate on, but he's got to start somewhere.

"Well. _Twice_ isn't the end of the world," says Erica.

Boyd snorts at her. "Trust you."

"What?" says Erica. "We've all done it _once_. You'll spend a day or two sighing whenever they think of you, but the connection isn't so strong as all that. Fades away in no time once you try someone new."

"And three times?" asks Stiles, with a sinking feeling.

Isaac and Erica exchange glances. "You could probably end it after three," Isaac decides, "but you'd be tempting fate."

"You'd have to ask Derek. He's the only one we know who's ever gone that far," adds Erica. "But if you meant to ask if we knew all along what was going on with Derek and _you_ , well..." The three of them trade significant looks, and Stiles feels oddly as though he's been invited to share the sentiment.

"He didn't even tell _us_ what was keeping him away until he'd been gone a whole month," Boyd explains. "Tried to play it off like he hadn't had any choice, when he finally came clean. None of us really bought it, but what can you do? No-one forced anyone into anything, and once the bond's sealed, it's set in stone."

Stiles feels a little like he's just been thumped in the chest. There's nothing like hearing the same bad news repeated by a new voice to drive the reality home. "There's no way to break it?" he asks, because he has to.

"That's kind of the idea," says Erica. "Besides, who'd want to?"

" _Derek_ sure sounded like he might," says Stiles, bitterly.

" _Stiles_ ," says Erica, returning again to that strange tone of infinite patience, "this isn't your fault, you know. Derek's not so easy to turn down, and you had no way of knowing what you were getting into."

"Lot of their kind put a lot of work into making sure of that," adds Boyd.

"Besides," Erica goes on. "Derek's a grown man – or close enough. He knew what he was doing. He wouldn't have given in to temptation if he hadn't seen _something_ in you he liked. Look at it that way, it's almost romantic."

"Binding yourself to the will of some unsuspecting guy is what you call _romantic_?" protests Stiles, disbelieving.

"Why not? It's as close as we're ever going to get," says Isaac. "Of course, you don't really know if the human you're bound to is going to play nice if until you try, and if you get it wrong, you don't get a second try. So most of us don't try at all. That's how it works for demons, in case you hadn't noticed: the rules bite both ways. Hell, they pretty much exist just to screw everyone over."

Stiles feels like there's something welling up inside him, something like hysteria caught in the back of his throat. That's what it all comes down to in the end, isn't it? He can plead he _hadn't known_ as long and hard as he wants, but there's no way he can pretend no-one ever warned him getting involved with a demon might be a bad idea. Like every taboo-breaking hero in every moralistic tale ever told, it's only the _why_ he'd had to find out the hard way.

"This was never Derek _trying_ ," Stiles spits. "He didn't plan any of this, he made that much very clear – he spelled the whole thing out as one long accident. I mean, I spent this whole time thinking _he_ was the one who was probably using _me_ – and he _let_ me think that! He hid it all from me for months and then he basically threw it all in my face!"

It doesn't really get him the reaction he'd been going for, though he does get to see Erica exchange glances with Isaac and Boyd again before anyone says anything. "That does sound like someone we know," Erica allows, once they're done.

"The thing you have to understand about Derek," says Boyd, "is he may do his best to play the inscrutable leader, but most of the time he doesn't have any more idea what he's doing than the rest of us. He's just not so keen on being reminded about it. Give him a few days – he'll calm down and come around." Boyd appears to consider this conclusion for a moment. "Or he'll realise this thing with you was a mistake to begin with and finally get up the guts to leave and not come back."

"I think it's a little late for that, Boyd," says Erica, though she does at least have the decency to sound less than impressed with Boyd's addendum.

"But we don't _know_ , do we?" says Boyd. "All your stories are about evil sorcerers seducing your kind and using the bond against them. Could be different with someone who isn't messing with them to force them to stay."

They both turn back to Stiles expectantly. "Well, Stiles?" prompts Erica. " _Do_ you want him to come back?"

"I don't know, okay? This doesn't work if he only comes back because _I_ want him to," Stiles blurts stupidly. "This is all – this is not what I thought I signed up for."

"Hate to break it to you," says Isaac, "but you want _is_ what he wants now."

"And I don't want it to work like that!" Stiles complains, though it really doesn't sound any less childish than it had in his head.

"You think that'd work?" says Erica, looking at the other two.

"I think if we all wanted what we _wanted_ ourselves to want, the world would be a pretty different place," says Boyd.

"'Want' officially no longer sounds like a word to me," says Isaac.

Stiles can relate.

* * *

He doesn't exactly manage to put the subject out of his mind for the rest of the day, but his talk with Erica, Isaac and Boyd had both clarified and confused the issue sufficiently that the mere thought of touching on it again leaves him mentally exhausted. Stiles makes it through the day largely on automatic, and collapses into bed that night without having experienced any new epiphany.

Derek doesn't reappear that night, to nobody's surprise.

The trouble with personal life-ruining epiphanies is that the world at large doesn't tend to appreciate them, so when Stiles wakes up again – now a solid thirty-six hours away from his confrontation with Derek – the rest of his problems have failed to spontaneously vanish after a mere twenty four hours of being studiously forgotten. By this point, however, throwing himself headfirst at their other supernatural problem instead has started to look downright appealing when compared to moping about his love life any longer.

One thing Stiles does have to say for their new staff – it's a whole lot easier to sneak out for a few hours for mystical werewolf reasons now that Boyd's running the household.

"Sure," he says, once Stiles and Scott have finished delivering a completely truthful account of everything they have planned. "Anything else you need?"

"Can we take Isaac?" asks Scott. "Stiles was saying, you know, strength in numbers."

Stiles' full argument had contained a few more details regarding the odds this stunt might attract them another volkodlak (or two), and how Scott would feel about having to rip off another head (or three) without backup. The fact that Stiles, personally, as one of the Tower's diminishing population of actual humans, would feel a lot safer with more supernatural muscle on his side is beside the point: the case for Isaac is an easy sell.

The case for not waiting to contact the pack again is nominally even easier, because no matter what's going on in Stiles' personal life, people are still dying and the hunters are still hunting the wrong target. This is a real and positive step he and Scott can take to safeguard their community, and there's no good reason to put it off. There are real and important reasons to get onto this quickly that have absolutely nothing to do with how badly Stiles needs to distract himself. That's really just a bonus.

The distraction would probably work better if Stiles could stop _thinking_ about how he's arranged this distraction for more than a few minutes at a time. He pushes that to the top of his to-do list.

"Okay," says Boyd. "Try not to take too long – explaining why you're all gone at once is going to take some creativity."

That's quite literally all it takes. He, Scott and Isaac are on their way in ten minutes flat.

There's a downside to bringing both Scott and Isaac that hadn't occurred to Stiles before they left, this being that it leaves him as the odd human out. After reminding the others to slow down several times during the first half of the journey he more or less gives up and saves his breath for the exertion. An additional downside beginning to nag at him with increasing intensity is that they have no idea how the wild pack might react to Isaac. They've yet to respond well to either werewolf or human emissaries, and it doesn't seem likely a demon will warrant a warmer welcome, but Stiles generally concludes he'd still much rather have backup along than not.

"First rule:" Scott tells Isaac, at the bottom of the hill, "if they do show up, don't antagonise them! They don't like us much and we need not to make it any worse."

"Not like I could do anything to them if I wanted to," Isaac replies, keeping pace just behind Scott as easily as if they were only out for a casual stroll. "Werewolves aren't much good to my kind." To Isaac's mind, 'I couldn't feed on them for sex even if I tried' is presumably a reasonable and unprovocative argument. Over the course of the journey, Stiles has gone from quiet gratitude that Isaac hasn't said anything that might hint to Scott about what he's going through on the Derek front, to a growing suspicion that Isaac's forgotten all about it. Stiles reminds himself there's a not inconsiderable chance he'll get to see something wolfy chew on Isaac before the day is out and enjoys the thought more than is probably good for the soul.

"You're still strong enough to threaten them," says Scott, "And – no offence – but 'your kind' aren't exactly known for being trustworthy either."

"What if we get more than werewolves?" asks Isaac, brushing the diplomacy issue aside. "This is how you met the first volkodlak, right? Am I pronouncing that right? Volkodlak? Volkodlak?" He looks at Stiles, who can only shrug back at him. He's still pronouncing it 'werewolf-vampire-zombie' in his own head more often than not.

"Trust me," Scott tells Isaac, as they come to a stop at the peak. "If another one shows up, you'll smell it coming."

"Smell's not actually one of those senses we get enhanced the same way yours is," says Isaac.

"Then trust _me_ ," says Stiles, huffing his way up behind them, "if you don't smell it coming, you'll smell it when it gets here."

"That bad?"

"Oh yeah."

Leaving Isaac with that cheery thought, they set up, and then they wait.

And wait.

Stiles is theoretically aware that declaring the waiting to be 'the worst part' would be premature when there's still so much of the day left in which for things to go horribly wrong, but the impulse only grows as the minutes drag on. Had it taken this long last time? He's leaning towards 'no', but there's no easy way to mark time out here. Stiles shifts his weight from foot to foot, sits down, changes his mind and stands back up again, and wishes he'd thought give himself a bit more space. The good will Scott (and Isaac) may earn by being discovered _not_ hiding behind a magic circle when the pack shows up probably isn't huge, but it can't hurt. Stiles, on the other hand, has no intention of being part of anything that might result in another accidental volkodlak summoning without a line of mountain ash between him and it. His circle was sensibly laid out to provide elbow room for a population of one; it's only now that he's begun to wish he'd allowed himself room to pace.

It doesn't particularly help to know that if or when something _does_ happen, Stiles is likely to be the last of the three of them to know. Eventually he gives up watching the scenery at all and takes up watching Scott instead, which is why he spots it almost immediately when Scott abruptly tenses up.

"What?" Stiles demands. "What's happening?"

Scott frowns into the middle distance, nostrils flaring. "I think..." he begins, then hesitates so long that Stiles is just about to point out that 'Ithink' is not a proper answer – and hardly even a proper _sentence_ – when Isaac joins the conversation.

"Do you see that?" he calls, eyes turned to the treeline. "There's something moving."

Stiles follows his gaze, and actually sags with relief when he recognises the silhouette coming out of the forest. "Hey, it's her again!" Unhelpful as she'd been last time, he'll take Scary Wolf Lady over an undead wolf of any shape or size.

"Stiles," says Scott, voice low and urgent.

"What?"

"Look closer."

Stiles doesn't look closer. He's looking at Scott's face instead, which tells a much clearer story. "Ohh no..."

"Yeah."

"This is _not_ good," Stiles mutters, now wishing only that he'd laid out his circle a little further away.

The werewolf's body staggers into the sunlight. With a clarity of the man who knows there is absolutely nothing he can do to help what's about to happen, Stiles notes that she – _it –_ doesn't look nearly so long dead as the last volkodlak. The flesh is a little warmer in tone, the dark webbing of her veins not quite so stark – she even moves more easily – but the flat, white eyes are unfortunately distinctive. Stiles watches as those eyes shift from Scott to himself, then finally to Isaac, where they linger – then the volkodlak hurls itself towards him with a choked-off scream of a howl. To Stiles' horror, Isaac is too stupefied to respond for what might be about to prove one moment too long – but Scott's already throwing himself into its path to intercept and all three seem to collide almost-

Stiles really doesn't need to watch the rest of this.

* * *

Volkodlak II doesn't go down any more cleanly than the first. It does so without coming within a few yards of Stiles, which is some small consolation, but not before slashing open Scott's chest, getting its teeth into Isaac's side and spraying them both with dark blood. Scott helpfully relieves Isaac of some of the pain, while Stiles considers the relative merits of throwing up.

No other werewolf, familiar or unfamiliar, alive or dead, ever appears.

"If _she's_ dead," says Scott, eventually, "what about the rest of the pack?"

"They could be in hiding, I guess," suggests Stiles, though he's not sure himself whether this constitutes wishful thinking. Every werewolf in that pack has survived everything the Argents could throw at them for years. To suggest a volkodlak or two could be more than they could deal with _should_ be crazy. But recognising the face of that rotting _thing_ as it came staggering out of the woods was a new and haunting experience even for him, and he never even knew her name. He doesn't like to imagine what it would be like to see a friend – let alone a family member – reappear that way.

Whatever's left of the pack, they're not likely to be in any state to respond to a strange howl in the woods for a long time.

"How many of them were there?" asks Isaac. "Was it a large pack or just one family?"

Scott looks away. "I don't know."

The real question, thinks Stiles, is how many of them will rise again if someone doesn't find a way to stop it, though it's all depressingly hypothetical from this angle. He doesn't have the first idea. He's hardly got the first idea how anyone would go about getting their first idea, and that shouldn't even be a problem because _none of this_ should be his problem to begin with.

He'd talked to Allison a bit during the previous day. It was kind of nice, actually – at least the part where she'd promised him (as someone who has emphatically Been There with regards to getting oneself romantically involved with supernatural entities of questionable reputation) she'd do anything in her power to cover for him, as long as this demon stuff went unresolved. She'd also taken the opportunity to point out that it wasn't going to mattermuch, from Derek or Lydia's perspective, whether the hunters found out about the _volkodlaki_ problem or not. 'Experts' who'd blame a demon-summoning on its first would-be-victim wouldn't hesitate to blame undead werewolves on the same origin – not when their victims provided such a convenient cover for demonic murder. Convincing the hunters that a sudden infestation of volkodlaki has nothing to do with the equally sudden appearance of two different incubi where none have been seen for generations isn't going to work, especially not when nothing in their own sources could suggest a better theory. Allison was only pointing out the obvious: no matter how you twist it, the timing looks _bad_.

If the pack won't (or can't) talk to them, then the best hope they have left of figuring out where the volkodlaki are coming from just went up in smoke. Unfortunately, Stiles' last remotely promising lead involves calling Derek back and reminding him about his promise to see if he could track something else down – a book or a rumour or _anything_. And Stiles emphatically doesn't feel ready to talk to Derek again yet.

Knowing he canmake Derek show up purely by wanting him to never made him feel sick before.

Okay, the smell of dead volkodlak wafting over the hill probably isn't helping either on that front.

It hits Stiles all in a rush that he's standing in the woods with a werewolf and an incubus, who he just watched tear a vampire-zombie limb from limb, while waiting for more werewolves who never showed up. They're going to go home to a Tower owned by a young lady who might well be a witch, all but emptied by a war he's never seen, and staffed by a succubus, a fae and a half a dozen hunters. Stiles could not feasibly be much further out of his depth and still breathing.

He's starting to miss the days when his biggest problem involved keeping Scott locked up once a month. Well, he tries to miss it. Makes a genuine attempt to convince himself his life was simpler back then, which quickly proves revoltingly unsuccessful. Ignorance may be bliss, but hindsight doesn't always catch its best angle.

Mostly he just misses Derek. Which is more or less the single most useless thing he could be doing with his time.

Back in the present, taking place somewhere on the trek back from the hill, Scott has more immediate concerns. "You think it's significant that we've only seen one at a time?" he wonders.

"You mean like, new zombie-wolves moving in as the territory becomes available?" suggests Isaac.

"I don't think so," says Scott. "Almost the only thing we know for sure is they were wolves that died here. She – the wolf we talked to last time made it sound like the first one was a pack member who rose from the grave."

The impression that he should possibly be taking part in this conversation hovers vaguely over Stiles without sparking much inspiration. Maybe Scott's on to something, but how's he supposed to _know_ , really? He's no magician, he knows barely enough to get himself in trouble. Once you subtract out every clever 'idea' he's had over the last few months that he really owes to Derek, Allison or even the hunters, what's left? One lousy plan to get Scott to aggravate the local pack and announce his location to the nearest were-zombie, and the dumb idea that volunteering himself as bait for an incubus might somehow work out. His record speaks for itself.

"Maybe the death of one summons the next?" suggests Isaac.

"Can that happen?" Scott wonders.

"I've heard of something like it happening with demons," says Isaac. "but we tend to like our bodies a little fresher. No idea if the same goes for volkodlaks."

"So if we kill one... another rises in its place?"

There's a nice thought. Scott's helped kill two volkodlaki, and it might not even have helped. Jesus. It's been over a week since they first started on this fool's mission to track down the real agent behind the murders, and they're not even sure if killing the evil monsters is a good idea yet. Which puts this about on par with the rest of Stiles' plans lately.

He has a go at feeling properly downtrodden about this great series of revelations about his value to the universe, but can't really get into it. It's not like it's news that he's never had any real idea what he was doing. It's been his ironclad excuse for getting involved with Derek from the start. Oh yeah, everyone tells you demons are dangerous. Everyone tells you not to trust them, because it never ends well. But no-one ever tells you the truth about _why_ , because that knowledge is _too dangerous to be known_ , so Stiles has spent their whole courtship with the stupid idea it was Derek he should be worried about, not himself.

The sick truth is that telling himself Derek was the one with the power, _Derek_ was the one with the ulterior motives, always made it that little bit easier to justify letting himself get caught up and dragged in; always gave him that out where he never had to take Derek's own investment in what they were doing seriously.

Stiles awareness of the conversation shifts back into focus mostly because it seems to have stopped.

"Stiles?" says Scott, for what may not be the first time. "What do you think?"

Stiles blinks at them, and pokes his recent memory for any echoes of intervening bits of wisdom he's evidently missed. Scott... did he say something about there being 'two of them'? Two volkodlaki? Because there were two deaths in the castle? Or just one that was really hungry? Was that Isaac?

What does _he_ think? Stiles thinks it's maybe hilarious that they're asking him at all.

"You realise the only other person left in the Tower who's not a werewolf or a demon or a hunter or probably-a-witch or something is _Jackson?_ " says Stiles, surprising even himself. "Have you considered asking _Jackson_? Because he is literally the only person in my life right now _less_ qualified to deal with this stuff than I am."

The silence that follows Stiles' hilarious observation has time to become distinctly uncomfortable before anyone says anything else.

"We... should really get moving if we want to get home before it gets dark," Scott decides, at last.

"Yeah," Isaac agrees.

They spend the rest of the trip not really looking back at Stiles any more than they have to, which suits him just fine.

* * *

So it turns out attempting to distract himself from his problems with werewolf-vampire-zombies was _also_ a terrible plan. Stiles adds that to his tally and hates his life.

Scott spends the rest of the evening giving Stiles as much space as reasonably possible. Word must've got around, because everyone else seems to be doing it too. This means Stiles doesn't have to pretend to be okay around anyone else, which is great, but it also means he's left to deal with his problems without distraction, which is less so. He's still thinking about Derek in terms of how much he doesn't want to have to deal with anything relating to the subject of Derek when Derek himself comes in through the window, not so very much later that night.

This presumably means Stiles isn't responsible for forcing him to show up by wanting it, which is something. Unless Derek's excuse is along the lines of Stiles not-wanting-to-want again, which was enough of a headache even at the time. Now? Stiles would possibly even rather speak to Derek than have to work that one through.

"Couldn't stay away, huh?" he says, by way of greeting. "And, you know, feel free to take that in whatever awkwardly literal sense works for you."

Derek hesitates by the window, looking out of place in Stiles' room in a way he hasn't in a long time. If he studies Derek's body language long enough, there's a real danger he's going to start coming up with virtually-coherent theories about whether the stiff lines of his posture mean he wouldn't be here without Stiles' influence drawing him in like iron to a lodestone; whether the set of his jaw or the line of his mouth speaks of a silent internal war against his own judgement; whether the number of seconds Stiles has already watched him silently gathering himself to speak mean anything that might reflect badly on how Stiles has handled this – or whether it's all just pure Derek, because he's always been this bad at talking to humans when he can't threaten or seduce his way to easy success.

This amounts to a great long list of excuses to do anything _but_ actually look Derek in the eye, which is probably why Stiles is quite so unprepared when the first words to come out of Derek's mouth are, "Look, Stiles, I. I owe you an apology."

"An apology?" In all of Stiles experience, Derek does not apologise. "You?"

"Some of what I said yesterday wasn't called for." Derek sounds like he's rehearsed this in his head a few times before he got here today, but underneath that he still manages to sound like he means it, and that more than anything else is what pushes Stiles over the edge.

"Right," says Stiles, faster and sharper than is probably called for. "Is that because you think you need to apologise for forcing me to pull my head out at last and face all that stuff I didn't want to know about, or because somewhere deep down _I_ want this to be something you apologise for, and I just can't admit that to myself? Because-"

"Because obviously there's no way I could have spent the last few months of my life asking myself those same questions on my own," Derek interjects, "over every damn impulse that crosses my mind without you to do it for me."

Stiles wilts, and feels awful about himself some more. "Okay. Sorry. That wasn't fair." Looking away is only partially something he does to avoid seeing whether Derek is rolling his eyes. They can be as sarcastic and flippant as they like with each other – that's all they ever seem to _do_ , and Stiles can't start pretending now that's more Derek's fault than his – but it's not going to get them anywhere. "I just don't know what I'm supposed to _do_ with this."

Stiles hears Derek huff, or sigh, or something in between. "This was easier when you didn't know," Derek admits, and the admission doesn't seem to come cheap. "At least then if you abused it, it couldn't be because you meant to."

"Guess that answers the question of whether you were ever planning on telling me," Stiles mutters, not un-bitterly.

"You were always going to find out eventually," Derek allows, though he doesn't deny what Stiles hasn't asked. "But you're not the one who got into this knowing. It shouldn't have happened at all. I should have known – I _knew_ better. This is on me, not you."

"So help me understand why you _did_ ," Stiles begs him, and means it like he's not used to meaning things he says to Derek. "I mean, if it was just because of Kate-"

"No." This comes out too fast, too easily for Stiles to hear it as anything but honest. Even now, something in his stomach jumps to hear Derek suggest this thing between them was no accident – even after lurching when he'd implied the opposite not a moment ago. Stiles has the premonition his stomach is in for a bumpy ride. "The geas was an excuse – it made it easy," says Derek. "I didn't have to come back to you that day. I didn't have to come back after. And it started before then."

There's a pause, Derek looks as though he might be deciding where to start.

Stiles gulps. Silences are bad. He always feels the need to fill them, for better or for worse, which is probably why he ends up blurting out, "Well, you know... what am I saying, of _course_ you know, but if it helps... you're not the only one who's spent this whole time wondering whether you should know better than get involved in this. We're in that much together."

Derek doesn't particularly seem to react to that. Stiles is still debating whether this means he's actually so deep in thought he wasn't listening when the bed beside him dips as Derek takes a seat.

"When you live like we do, seduction – sex – is just routine," Derek begins. "Like eating and sleeping. I've fucked more people than you've probably ever met. I've been with people who were flattered, who were desperate or broken, who were terrified of being caught. With men and women, with both at once – couples, widows, virgins – every age old or young enough to remember how to want what I can give them."

Presumably, Derek is building to a point. Stiles certainly hopes so, anyway. "Is this-"

"Helping you understand," says Derek, soft but firm, before picking back up from where Stiles cut in. "I've been with people who wanted me from the moment I walked in; who hated themselves for it; who hated me for the crime of making them want me. I've lost myself in people who would've used it to punish both of us for our transgression. I've revealed myself to those who deserved it – it's no reward to them, Stiles. I've killed those who deserved even less. I've lived by the rule that you never look back as you leave."

Derek takes a breath, and looks at Stiles, with an intensity that makes all impulse to interject again die on his lips. "Do you have any idea how many people I've been with who knew what I was, who knew I wasn't a dream, and wanted me anyway?"

"Not many?" Stiles hazards.

"Just you," says Derek, and lets that rest between them before he goes on. "Before you even saw me, you knew what was coming – and you were there anyway. Willing to look me in the eye without running. You hardly needed an excuse to say _yes_."

"I was there because I was trying to kill you!" Stiles protests, because this seems to be a point Derek's missed somewhere along the line.

"You were trying to kill someone else," says Derek, reasonably. "Don't get me wrong – it was a stupid thing you did that night. It nearly got you killed, and it was _fun_ to be able to show you how wrong you were. But you learned and adapted faster than you had any right to, and when I went back to you after that hunter, after we both came so close to giving me away, you weren't scared of me anymore."

Stiles feels a little like they must be remembering different events. "I asked if you were going to kill me three times! You threatened to walk out on me if I didn't shut up!"

"And you _still kept asking questions_." Even now, Derek sounds as though he can't quite get his head around this fact. "You were nervous, cautious – that's not the same as being scared. You were aroused and facing down a demon, and still you needed to understand so badly you never stopped, not until I'd given you my _name_. You were fascinated. You wanted to understand me as much as you wanted me. That was... fascinating to me too.

"I thought I'd be able to leave after that. I thought if I gave you just twenty four hours, you'd do _something_ to make it easy for me. Instead I caught you pining after someone else who never even noticed you. You found someone _you_ wanted choosing someone else over you; when you had no idea what that was like for me, and I had to show you."

Derek's never voluntarily brought up that incident in the hallway outside Lydia's room since it happened. Stiles hadn't thought of it as a turning point – he hadn't thought about it much at all in a long time – but Derek's version doesn't strike him as unlikely. "Not good for your ego, huh?"

Derek nods, absently. "Maybe that was my one mistake with you."

"Derek," says Stiles, "if that was a mistake, it was a pretty big mistake."

Derek doesn't argue. "After that, it was only a matter of time before you realised how easily you could call me back. There was no ignoring what you were feeling."

Stiles digests this, or tries to. "You don't even seem to _like_ me most of the time."

"You frustrate me. You confuse me." Derek shakes his head and huffs. "There isn't a damn thing about you that makes sense to me, Stiles. You'll leave mountain ash out like it's a joke to you, you'll invite in a demon and interrogate me on – on something you found in a _dictionary_ , for god's sake. I thought there'd be a tipping point, when I'd seen and felt enough that you made sense to me, but before I became attached. But there never was."

"Derek," says Stiles, something like laughter bubbling in his throat. "Even _I_ don't understand me most of the time."

Derek smiles, or half-smiles, the look strange and distant. "The truth is it wouldn't have been nearly so easy to let myself get caught up in this if it wasn't obvious you were going to hate knowing what it meant."

"No, I get that," says Stiles. "You'd be nuts to trust someone who wanted that kind of power over you, so who does that leave?"

He watches Derek nod and look away again. "Stiles, if I'm honest, a part of the reason why I didn't tell you is that I knew that if I did, there was a chance you'd find the resolve to do what I couldn't and end this thing between us before it got too deep to shake. You couldn't trust me, and I couldn't tell you you should. Not until now."

"What, and you trust me _now_? Now I could – could make you trust me by wanting you to trust me? That's how it works, right?"

"I'd like to trust you anyway," says Derek, softly. As if he has a choice. As if just because Stiles probably hasn't ever pressed the advantage with him before, because he probably won't mean to when he does, that means he never will.

Stiles does get what Derek came here to tell him today. It's different, all laid out this way. This is Derek saying _if I'd had a choice, I think I might have wanted you anyway._

It would be nice if he could trust that much himself. In the unlikely event that he ever becomes so famous for the dubious honour of having someone base a play on his life, Stiles thinks, he'd give even odds on whether it would be a tragedy or a comedy.

"God," he mutters, feeling at once tired and helpless, "I spend all my time worrying that I'm just feeling what you want me to feel, and now I find you've spent the whole time worrying that _you're_ just feeling what _I_ want from _you_ , and I just – why did either of us ever think this was a good idea?"

The smile Derek gives him is slight and uncharacteristically sheepish, the hand he slides to rest above Stiles' knee hardly less so. "I could remind you."

Stiles laughs at that, because he can't not laugh at it. He says, "This is such a bad idea," but he's reaching for Derek even as he does it, even as his conscience stretches and tugs, holding him so that he falters before his fingertips reach his mark.

The voice in the back of his head saying that this matters – that what he does now _matters_ – isn't easily shaken. Even if it's crazy to suggest it could be so simple to end this now, the way Boyd had suggested, he has to ask, "If I said no, would that...?"

The look Derek gives him is so terrifyingly open that Stiles can't even finish that thought.

"Yeah," he says, "I didn't think so."

He knows, as he lets Derek tug him into his lap, that this isn't going to make it all okay. But nothing's going to make this okay anymore, and this is all they've got.

* * *

It's different, this time. And it should be, but just how different is more than Stiles is ready for. Maybe neither of them really imagined they could just fall back into the rhythm of this like nothing had changed, but losing himself in it like he kind of wants to quickly proves impossible. Stiles aware of everything like it's new again; what they're doing feels transgressive in a way it hasn't been in a long time. He isn't completely sure whether this is Derek still apologising, or whether this is _them_ from now on, with no more secrets left to pad the space between them, but the way Derek handles him tonight is reverent – almost grateful – and Stiles can't shake the feeling this is him searching for reassurance that he won't be sent away.

Stiles doesn't know what to tell him. _I know I should but I don't think I could go through with it_ wouldn't come across that well, and anything less would be a lie.

This is, of course, the perfect time for Stiles to have chosen to develop a startling new awareness that what they do together _shouldn't be_ this easy. He shouldn't be able to just sit back on his knees and sink down onto Derek like he belongs there; it shouldn't be nearly so easy for Derek to keep them both comfortable, shifting them in micro-adjustments before any part of Stiles' lower body can get beyond the first threats of cramping – or for Derek to curl up and around him, to catch Stiles' mouth and kiss him just when he wants it most. Derek is amazing, and sex with Derek is amazing – having Derek inside him like this is the kind of unspeakably amazing experience that bad poetry is born of – and to think that Derek only touches him the way he does because he feels how much Stiles likes it is heartbreaking. It doesn't seem fair that Derek wants what _Stiles_ wants, has to and can't help it.

Everything about Derek is literally too good to be true.

"I was hoping I could get you to think a little less," Derek admits.

"Yeah," Stiles breathes, in a gust of laughter, "good luck with that." With a flash of guilt, he realises he has no idea how much of what he's thinking Derek might be getting. He's got the idea it's possible for him to hide things from Derek if he doesn't want them known, but how far does that really go? Would it be better or worse to use it? How much control does he really have?

He loses that thought on the end of Derek's next rolling thrust – catching him somewhere deep inside with new intensity – though he doesn't find much cause to miss it once it's gone. " _Oh my god_ , you're good at this, have I mentioned that lately?"

Derek's smile is more soft than smug. "I'm aware. Don't let that discourage you though."

Stiles still has enough leverage to move on his own initiative, but he's getting to where he forgets to, caught between Derek's hips – picking up where Stiles falters with nary a break of rhythm – and Derek's hand, in a pattern of stroke-and-release calculated to keep him just this side of the edge. For all that Derek's taking nearly all his weight, what he's doing to Stiles is all fluid motion and with all his senses focused elsewhere the combination throws his equilibrium into a kind of ecstatic freefall. Derek's skin under his hands is all he has to ground himself, the pale underbelly of his chest so tantalisingly close, and Stiles wants to get his mouth on it – he _wants_ to be the one making _Derek_ come sometime, with only his hands or his tongue – the thought comes to him all in a rush. He can't bend himself nearly far enough to reach him now – not even Derek can make that possible, but he can curl a hand over Stiles' own shoulder and dip his tongue along the line of Stiles' collarbone, up the nape of his neck – and he does, and Stiles loves it. He looks down, at Derek moving under him, into him, and marvels. He can't imagine how anyone could give this up.

Hopefully _that's_ going to be one of the parts Derek gets, if any.

"The feeling is mutual, I promise you," says Derek, which works on so many levels of double-meaning that Stiles laughs at him some more.

Cliché as it might be to say _until we can't tell where one of us ends and the other begins anymore_ , that's... just about literally how this works, for Derek. Has always worked. Can't ever _not_ work again, if Stiles has understood correctly.

"So I'm glad I _know_ you get off on me getting off, like, that's what it's been about with you all along, or I could be really starting to wonder now I know you-" Too late, Stiles hears what he's saying and cuts himself off – sex brings out the babbling, and a babbling Stiles is never at his most tactful, _least_ of all under stress – but Derek seems to take it in one of the better senses available.

"Stiles," he says, easy good humour in his eyes as his free hand ghosts idly over the contour of Stiles' back, "there's nothing supernatural about sex with someone who likes making you enjoy yourself. Not if you're with anyone any good – with anyone who sees you as more than a warm body. Humans aren't asuniversally selfish as all that."

"Yeah?" says Stiles, vaguely. Derek's thrusts are a steady, warm pulse inside him; his voice a hypnotic lull Stiles could listen to and lose all track of time. The urge to keep Derek talking is, for once, overwhelming any need to fill the silence himself.

"You don't think I'd know?" Derek's face may not be smirking – he may make this sound as matter-of-fact as the sun rising in the east – but Stiles can hear one anyway.

"Oh, of course," he breathes, "any excuse to remind me how many people you've been with again-" The rejoinder is automatic, honestly – Stiles may still be drifting back and forth on how he feels about the idea Derek is _his_ , morally speaking, but the reminder is there in everything he does now, and in the moment the effect is a little breathtaking.

"Who weren't worth coming back for?"

Derek's new found talent for switching between smug and sincere so quickly is doing awkward things to Stiles' few remaining defences. "Seriously, not anyone? You weren't even tempted?"

"We're always tempted," says Derek. "But believe me, Stiles, there are men and women out there in the world who'd leap at the chance to see you like this," he whispers, but Stiles doesn't have time to process that much before he adds, much softer now, "If you ever do this with someone else, maybe you'll notice."

Stiles' heart seems to physically clench in his chest. "Don't even joke about that! We're both tied into this now, there's not going to be anyone else."

" _I'm_ tied in," says Derek, not quite making eye contact. His hand is light against Stiles' cock, letting the motion from below alone press them together. "You're not. If you wanted to... experiment, I wouldn't stop you."

Stiles doesn't feel like he has any idea where this came from. Derek has _got_ to know what a bucket of cold water he's finding this whole topic. "It'd still _hurt_."

"What's the worst that could happen?" says Derek, oddly distant, his other hand stilling on Stiles' hip holding him only lightly as they move against each other. "If you found someone you liked better, stopped wanting me... at least we'd know how much of this is mine."

Jesus, is this Derek being scared Stiles might get _bored_ with him? That his fixation on Derek is all inexperience, and that he might be happier with someone else? Even after all this? But Stiles doesn't get totell Derek not to think like that – not anymore – because what would it mean if Derek obeys?

Never has Stiles been more aware that the link between them only goes one way. Just when he thinks he gets it, Derek finds new ways to confuse him, mixing his messages until Stiles can't make head or tail of him.

Can he really do this at all?

He comes with his arms around Derek's shoulders, his face tucked into Derek's neck, holding onto him through the aftershocks for dear life.

By the time he falls asleep that night, he hasn't let go, and Derek has made no attempt to make him.

* * *

That last detail doesn't quite become notable until Stiles jerks awake some hours later to the sound of someone banging hard on his bedroom door, and the discovery that Derek is still lying wrapped around him. Because Stiles is still getting used to the new status quo where more than half the Tower's inhabitants are in his corner, he doesn't really have time to make sense of this before surprise gives way to automatic and urgent panic because _Derek is still in his bed and someone is knocking on the door_.

Derek deftly ducks and pins both of Stiles' flailing arms, puts his mouth to Stiles' ear and breathes the words, "It's only Scott," before Stiles can do either of them an injury. 'Only Scott' could, unfortunately, still hear clearly if Stiles takes this opportunity to ask Derek what he's doing, so he doesn't. But Derek does slip out of bed all the same, kisses Stiles once on the forehead, and slips away out the window in an unhurried sort of fashion, which he nonetheless completes before Stiles has quite finished disentangling his own self from the bedclothes.

Scott's stopped knocking by the time Stiles gets to the door. Evidently, he didn't come back last night, though that hasn't been unusual in recent memory – Scott has long since mastered the art of slipping out of his own window and in through Allison's with a grace even Derek would probably have to respect. The furtive look in his eyes when Stiles opens the door suggests it may have dawned on him that Stiles hadn't woken up alone – if so, he's only second in line for that revelation after Stiles himself – but it does leave him slightly tongue tied by the pressing need to _not_ ask about it, which limits conversation not far beyond to superficial pleasantries. Having woken up feeling simultaneously better, worse, more enlightened and infinitely confused about the Derek situation in so many variations that whole head feels like its been stuffed with wool, this actually suits Stiles just fine. This feels like the sort of morning where waking up properly could take all day.

Actually, it only takes an hour or two for it to occur to Stiles that, even by recent standards, the Tower seems awfully quiet. Scott puts down his load of firewood and blinks at him when he points this out.

"The hunters left first thing this morning – you know, hunting?" Scott reminds him. "They were talking about it all last night at dinner, remember?"

Stiles concedes the hunters very probably had done something of the sort – not being Scott, the minutiae of the Argents' schedules doesn't necessarily have the same impact on his life. "All of them?"

"Everyone except Kate, but she was saddling up earlier too – I think she and Boyd had an errand to run in town or something?" The details can't have made much of an impression on Scott, and were probably related to something tedious and stewardly in any case. "So, yeah, it's just us, Isaac and Erica, Lydia and Jackson and the cook left today..."

Stiles goes very still. The corner of something that would have barely qualified for a half-formed idea last night has just acquired the urgency inspired by a narrow window of unique opportunity. "Scott," he says, "can you cover for me a while? Just remembered this thing I have to do."

"Cover from _who_?" asks Scott.

Stiles doesn't reply; he's busy making for the stairs with all the haste warranted by the likelihood that there's a rapidly closing window of time before he thinks better of what he's about to do. He takes all four flights two steps at a time, and gives himself only three seconds at the top to catch his breath at the top before pounding on Lydia's door.

"I really, badly need your help," he tells her, as soon as she opens it.

"Because?" Lydia prompts him.

Stiles shuts his eyes and blurts out, "Because I may have accidentally bound an incubus to me and I need to find a way to undo it and there's _no-one else_ I can ask."

For several terrible seconds, Lydia is silent. Stiles peeks nervously from under his eyelids, and considers the very real possibility she's going to slam the door in his face, and that he's wasting valuable time that could be better used to plan his escape route before the hunters inevitably come looking for him. The slam doesn't happen, but Lydia's expression remains inscrutable as ever.

"Hm," she says at last. "I suppose you'd better come in," and steps back from the door to let him pass.


	12. Chapter 12

Stiles takes two steps into the room and shuts the door behind him. Lydia has her arms folded beneath her bust, watching him in much the way Stiles remembers once seeing her watch a juggling minstrel from a past year's fair, upon hearing the rumour that several of his audience had found themselves missing their purses at the end of his last performance..Or perhaps the way an owl might watch a mouse that was trying to sell the idea that the mice found _over yonder hill_ were infinitely plumper and a bit slow.

Stiles often wishes he hadn't been cursed with quite such a vivid imagination.

"Alright," says Lydia. "Talk."

Anyone would think Stiles ought to be getting better at this part by now, given that this makes the third time he's had to do this in less than a week. Anyone, that is, who didn't know Lydia Martin. Stiles is starting to regret not having planned this far.

"His name is Derek," he begins. "He's the one who really killed the other one who attacked you that night." He risks a glance at Lydia's face, having unthinkingly defaulted to the humble servant's posture of turning his eyes to the floor, and shifts his weight self-consciously. "Obviously, this has been going on a while. I had no idea what I was really getting into at the time, I swear."

Lydia remains impassive as she absorbs this first volley of information. "And I should believe this wild tale because...?"

This is emphatically not the aspect Stiles was most expecting to be called upon to justify. He blinks at Lydia and blurts, "Because... but... you knew _something_ was going on! You have to have known! I _know_ you know I lied to you about what really happened that night. And then I lied again, which you also know, but it's not like I had any choice. I was under a geas! That I'm not under anymore, obviously. Derek let me out of it – he's really loosened up since he got to know me better. And I guess since I accidentally _bound him to me_."

"Which you did... _by accident_?" If someone had pricked Lydia with a pin in that moment, she might have bled pure skepticism.

"Funny story," says Stiles (because it's _hysterical_ , really), and fights the impulse to rub his face, which he can feel colouring slightly, "It turns out it's actually much easier to do than most people assume."

Lydia raises her eyebrows expectantly.

"And I'm not really sure if I should be telling you exactly _how_ it's done before you've decided if you're even going to help me," Stiles clarifies. "Derek wasn't happy I found out about it at all, and Allison didn't even _want_ to know how it was done."

That last part Lydia was obviously not expecting. "Allison... the hunter?"

Stiles takes a deep breath. "She found out about Derek by accident; she promised not to tell the other hunters – it's complicated, but we're good. I didn't even know binding demons to people was a thing until she told me – that's how unprepared I am for all this." Stiles scuffs a foot against the floor. More seems to be called for. "And... well, if I _had_ known, Derek would probably never have risked sticking around long enough to risk getting bound anyway. So that's kind of where I'm at." He hesitates here, but because Lydia is apparently playing dumb and because he might not find a better place to drop it into the conversation, he adds, "Allison also says you might be a witch. Well, that your mother was. A witch. And she might have left you some stuff. Relating to demons. If you were going to ask why I brought this to you."

Lydia makes no move to either confirm or deny any part of this. "And the young Miss Argent shared all this very secret hunter information with you, why?"

"Because the hunters think _you're_ the reason Derek's still around!" A little late, Stiles remembers that, even with all the hunters away, shouting this conversation probably isn't terribly wise. He drops his voice before finishing, "But it's not, it's because of _me_!"

Lydia narrows her eyes and looks him briefly up and down, as though perhaps double-checking that he hasn't sprouted goat's feet while she wasn't paying attention. "Not that this isn't fascinating stuff, but perhaps you could explain to me again what I'm supposed to do about it?"

Belatedly, it occurs to Stiles that he's possibly allowed himself get a little side-tracked away from the point. "Look, I know you helping me _un-_ bind myself from Derek isn't going to fix everything at once. It might not even be possible at all. But I don't know how else to make this right. It has to be worth a try. Doesn't it?"

The look on Lydia's face suggests she finds this proposition doubtful. "Alright, Stiles," she says, examining her nails. "So, supposing, for the sake of the argument, everything you say is true: supposing I was, in fact, a witch suspected of demon-summoning, living in a Tower full of suspicious hunters – hunters who _are_ , by your own account, already invested in proving my guilt. Supposing you have all that correct – I'd want to risk getting involved with your demon problems, _why_ , exactly?"

Stiles flashes rapidly through any number of justifications that might sell the idea. Because he and Derek saved her life? Because they're all in this together? Because getting Derek out of the picture could only be good for Lydia, too? Because there – like he said – is literally _no-one else_ he could hope to turn to? He takes a deep breath.

"Because I'm pretty sure no-one's ever tried this before, and if we don't, no-one might ever know if it's possible at all?"

Lydia tilts her head and treats Stiles to a long, thoughtful look. "Now _that's_ a bit more like it. Shall we get started?"

* * *

The hunters never did find the former Lady Martin's magic books. That's because to this day, they're sequestered carefully away in her daughter's room.

Stiles doesn't get to find out exactly where or how they're hidden. Presumably, there must be some sort of secret compartment – somewhere the hunters wouldn't have found when they searched the place – but Lydia makes him wait outside the room while she retrieves them. Stiles does his best not to feel offended. Yes, they may nominally be on the same side, at least as long as they're both harbouring secrets the hunters would have their heads for, but 'I am literally in bed with a demon, and I need your help to get myself out of it,' is never going to be the ideal way to convince people they should trust you.

Maybe more to the point, what he doesn't know can't be extracted under pain of torture. Lydia's always been that sort of pragmatist.

Lydia's secret trove consists of three old, leather-bound books, one titled in Latin and the other two blank and unlabeled; all three laid out on the bed in front of her when she calls him back in again. The books have been placed deliberately closer to Lydia's side than to Stiles', clearly conveying 'look, but don't touch' by placement alone. Stiles' fingers positively itch nonetheless.

"Magic," says Lydia, indicating the nearest of the three volumes, "Advanced Demonology," this second book is much larger and thicker than Stiles' own bestiary, which boasts barely a dozen pages on demons altogether, "and a compiled history of notable occurrences, business dealings conducted, and magical findings as recorded by four generations of magicians to come before us." Lydia's hand lands on the third book with a ringing slap that makes Stiles' fingers twitch with pre-emptive guilt. "Let's get a few things straight before we begin, Stiles. Do you have any concept of precisely _how_ forbidden what you're asking of me might be?"

"Um." Stiles swallows, thinking of the way the hunters tended to treat even 'ordinary' accusations that some unpopular local peasant might have brought themselves some minor good luck, or perhaps caused a neighbour's cow to go briefly dry, via some unlawful dabbling in the occult. Allison's take on the subject – to say nothing of Derek's – hadn't left a whole lot of ambiguity as to how far beyond the pale he's already ventured, unwittingly or no. "I think I have a general idea, yeah."

"Do you?" Lydia asks, pleasantly, as she begins to walk around the bed. "Let me tell you a thing or two about the woman who used to own these books. The former Lady Martin counted among her various magically afflicted clientele a not insignificant number of actual demons. It won't surprise you to know that she prided herself on her possession of an encyclopaedic knowledge of the nature, history and relative malice of _every_ demonic species common in this part of the world, not to mention several nigh-unheard of. This book," arriving beside Stiles, Lydia tugs the second of the volumes towards them and sits herself down on the edge of the bed, "contains an _extensive_ account of the physiology, predilections and specific weaknesses of the common succubus or incubus (as the species is traditionally distinguished by sex of its host). As you might imagine, she would have been intimately familiar with every word contained herein – however, as a gesture of good faith toward the more favourably disposed of her clients, there is one section of this book she had sealed upon acquisition, and never read."

Opening the book in question, Lydia flicks through the pages to draw Stiles' attention to a place where the open edge of a good number of pages have been gummed together with a long line of wax, rendering them inseparable.

"Would you care to surmise the subject of this chapter?" offers Lydia, sweetly.

Stiles would eagerlysurmise the content of that chapter. It's plainly the same subject Derek wouldn't even broach with him until he'd heard it already from an outside source; one that the hunters pass on only by word of mouth.

"Your mother really dealt with demons?" he blurts, without having really meant to. There are so many exciting questions jostling for focus in his head right now that he hardly knows where to start.

Lydia sighs at him, short and impatient. "My _mother_ believed that, inasmuch as peaceable coexistence is practicable with the demonic entities, the devil you know is infinitely preferable to the devil you _don't_ – and if that devil owes you for magical services rendered – well, so much the better. There will always be magics they can't perform for themselves, and for all their worst characteristics they _can_ be bargained with. The one thing you can say for demons is that they do keep their word – if not necessarily in the spirit you intended, which is all the more reason why someone who knows what she's dealing with should be the one to do the bargaining. She _believed_ , in short, that the world requires skilled intermediaries between good and evil to function without devolving into chaos."

"Is that what you believe, too?" Belatedly following Lydia's example, Stiles sits himself down in the nearest available chair. He can put his hands on his knees that way, and curb some of his more excitable impulses.

"It's a fine theory," says Lydia, icily, "but speaking personally? I can't say I particularly believe that any of my mother's principles are worth risking my neck for. Call these my inheritance if you must, but you might do better to think of them as incriminating evidence left behind when the former Lady Martin had to leave in a hurry."

Though this is a perspective somewhat at odds with Stiles' own burgeoning enthusiasm, he can't entirely blame her. Possession of any one of those books could have her hung by the neck – or worse. "Did you ever think about destroying them?"

Lydia gives him a long, hard stare before lifting one of the volumes. "This book contains a detailed description of fourteen distinct species of demon known to appear in this part of the country – many having _incredibly_ specific weaknesses rarely recorded elsewhere, including the exactpredicted dates of the next appearance of _three_ species known to manifest here only in cyclical fashion on a regular interval exceeding one hundred years. Personal annotations recorded in here by my mother's ancestors suggest that at least one of those demons may, on their next appearance, be expected to harbour less than fond feelings toward my family line." Replacing the book, Lydia lifts another. " _This_ book was entrusted to my mother as payment for services rendered to a demon whose name was not recorded, under the specific condition that the book itself never thereafter be removed from this tower. What precisely might occur if the book ever _was_ removed my mother also failed to record, however..."

"Okay, yeah, I get the idea." Whatever she might say, Stiles would bet several of his fingers that Lydia knows those books every bit as well as her mother ever did. There's no way she came upon an answer as detailed as the one she just gave him without giving the matter more than its share of thought.

"I _am_ willing to help you, Stiles," says Lydia, "but if I do, you'd best appreciate exactly what that means. I don't know exactly what's hidden in those sealed pages, but I'll promise you now it won't be the easy solution you're looking for. If such a thing had ever been done, my mother's clients wouldn't have been nearly so afraid they might ever find themselves needing it."

Stiles nods, already distracted by his own thoughts. It's not that he's not taking her warnings seriously – he is, absolutely – but there's a tingle like pins and needles building in the base of his stomach, and he wouldn't even be able to pretend it had more to do with fear than excitement. "Okay. Where, um. Where do you want me to start?"

Lydia crosses one leg over the other and appears to consider the question briefly. "I think you'd best start by explaining how someone goes about _accidentally_ binding a demon to oneself, don't you?"

So Stiles tells her. Lydia listens in polite silence until he's done.

"Hm," she says, when the ramble of words comes to an end, which isn't really the response Stiles has been steeling himself for since his answer began. He's expecting questions, any second now, but maybe Lydia's still thinking it through?

What she does instead is to reach for that oh-so-important demonology book and flip it open again. Producing a small knife from somewhere, she and deftly slices a neat line along the sealed edge off the pages which make up the hidden chapter. Stiles watches, dumbstruck, as Lydia lifts the book and begins to read. After a little while, she turns a page. Eventually, she puts it down again.

"What do you know," she says, quite without outward emotion. "You were telling the truth."

Lydia actually warms to the topic fairly rapidly after that, which comes as a great relief.

For the next hour, she has Stiles lay the whole progression of events out for her, fielding questions throughout, and finally sends him away with the promise there's nothing more she can do until she's had time to go back through her sources again.

Stiles leaves feeling both exhausted and hopeful in a way he hasn't felt in months.

* * *

Though the rest of the hunters aren't expected back at the tower for some days, Boyd and Kate are back by dinner, and dinner thus provides Stiles the opportunity to learn something new about their singular remaining Argent: absent her brother, niece, or any other figure whose respect matters to her in any meaningful way, Kate becomes... more _Kate_.

She mocks Jackson when he appears (late and long after everyone else is seated), and winks as she promises that the rest of them "won't start getting ideas just because you and our young lady show up together." Jackson sets his jaw and ignores her. Kate's account of her excursion with Boyd quickly provides the excuse to suggest she wouldn't mind "spending more time alone with him". Boyd politely pretends to have missed her meaning, then even more politely alludes to the professionalism expected of his position, and finally, with a class of manners that could be used to chip solid ice, tells her a very definite _no_. Unperturbed, Kate turns to Lydia, and insinuates that they two women might have "more in common than they used to," obviously looking at Jackson all the while. She goes on to offer that she (Kate) could make herself available to provide "advice" on the matter any time she (Lydia) might find she needs it. Lydia borrows a page from Boyd's book of manners and deflects like the side of a castle.

From the impartial servants' point of view, it's like something from a farcical comedy – funny in all those ways that everything is briefly funny while the ale is still flowing, and tomorrow's regrets are comfortable long hours away.

Come to that, Scott's starting to look like tomorrow's regrets have set in early. Stiles elbows him gently and asks if he's okay.

"The way she's talking, something about it's making me all..." Scott whispers back, with an elaborate shrug that manages to communicate 'werewolf problems' with reasonable clarity.

Stiles' stomach drops. Scott's control is good enough these days that he's not that worried, really, but it's that much harder to convince himself he's reading a little much into Kate's comments if Scott's reacting to it, too. "Is this that surrogate-alpha thing again?" he whispers back, volume pitched for Scott's ears only. It wouldn't be the first time Scott's taken implied insult toward Lydia a little personally, but it's different when it's Chris who's guilty – he's never liked Scott, so it's no surprise to see him get Scott's hackles up so easily. But Kate _likes_ Scott – she's usually the one playing peacemaker when there are sparks flying between her brother and Scott or Lydia.

"Maybe," says Scott. "Probably? It's more..." he shakes his head, "I'm even feeling bad for _Jackson_ right now."

Stiles kind of does too, come to think of it, though he'd really rather not.

That he's had to rethink a few of his assumptions since his confrontation with Allison in the woods goes without saying, but Stiles would rather hope he could be forgiven if he's still digesting some of the more abstract implications a mere three days later. Sifting through how much it explains about the Tower's complex internal politics hasn't exactly been at the top of his priorities since. If it had occurred to him to be suspicious that the hunters would elect to leave Kate behind for what amounts to routine guard duty while several more obvious candidates ride out to hunt a monster that had already claimed two of the Tower's own, the reason was almost too obvious to demand further examination. It's only now that he's found the need to put words to the fact that it's got nothing to do with providing them adequate protection, and everything to do with watching Lydia – watching her and hoping that with the rest of the hunters away, _this_ is when she'll finally let something suitably incriminating slip.

Standing there watching, as Kate boldly throws innuendo after innuendo at a room where everyone's hiding something far worse than anything she insinuates, it's starting to sink in with Stiles just how careful he and Lydia are going to have to be.

"Does she even notice there's no-one else laughing?" Scott whispers to him, and he's got a point: it's not often you see someone enjoying so much obvious merriment at their own wit, while every other person present uncomfortably avoids eye contact.

Wait – _almost_ every other person.

"Jesus," Stiles mutters, and shoves his serving jug into Scott's hands. "Hold this." He marches himself to the other side of the hall without waiting for a response.

Though they'd been called upon to assist the cook earlier, in theory Erica and Isaac should still be down in the kitchens now, since they aren't needed to wait upon the few remaining high-ranking folk dining in the main hall tonight. In practice, both of them are lounging just behind the doorway leading to the downstairs corridor, trading nudges and grins at events within the hall like kids discovering a kindred spirit.

Stiles backs himself up against the wall by the doorway so he can keep an eye on the high table while he does this, and – with any luck – keep himself from forgetting the genuinely pressing need to keep his voice down. "So. You've met Kate," he hisses to his left.

"She seems fun," says Isaac.

"More than most hunters by half," Erica agrees.

"Yeah, that's what Derek thought," Stiles informs them. "Right up until she _stabbed him in the chest_ and got us all into this mess!"

"So that was her?" Isaac, to Stiles great chagrin, does not seem to take this information with nearly the gravity it deserves. "Had a feeling it might be."

Stiles is struck by the sudden, horrible idea that by sex-demon standards, there's very likely no comeback better than fucking the responsible party without being found out. Or at least, not found out until after the fact.

"Is this a good time for me to remind you about the no-sex clause of our agreement?" he hisses into the doorway. "That's no sex with _anyone_ who lives in the Tower. Even if you're outside the Tower at the time."

"Shame," says Erica, but before Stiles can even begin to formulate the explosion that deserves, she adds, "Oh, by the way – Lydia asked me to pass on a message. She wants to see you after dinner."

The speed with which Stiles forgets all about Kate would likely do terrible things to her ego. Shame it's perhaps the one secret left in the Tower with almost no chance of ever coming out.

* * *

Stiles arrives in Lydia's room thrumming with nervous anticipation.

"Close the door," says Lydia.

Stiles does. Lydia is sitting on her bed again, the books no longer in evidence. Stiles tries to find an interpretation that makes this not a bad sign. "Did you find anything?"

"A number of passing allusions to the subject in other chapters regarding incubi, which I'm now seeing in a new and fascinating light," says Lydia, affecting a look of studious disinterest – and it dawns on Stiles in an uncomfortable moment of clarity that he may have convinced her to help, but this is still his problem, not hers, and she's going to make him work for everything he gets. "The sealed section had more to say on the subject of prevention than cure."

Stiles has not gotten this far in life by avoiding the obvious questions. "Well... did it say _anything_ about a cure?"

"The murder of one or both parties involved was considered a reliable solution." Lydia's voice suggests no particular feelings on the matter one way or the other.

"That's it?" Stiles' heart sinks.

Lydia shrugs. "There's plenty in my sources on the formation and dissolution of _traditional_ demonic bindings. But since a binding to a human's will turns out to work by other means altogether, that's less useful to the cause than we might have hoped."

"'Traditional' demonic binding?" Even if this point is every bit as irrelevant as Lydia seems to think, Stiles' curiosity is officially piqued.

Lydia flicks him a look from under her eyelashes. "A demon soul can be bound to a physical artefact – say, an item of jewellery, a monument – you've heard of this, yes?"

Stiles nods, eager both for her to go on, and for himself not to look wholly uneducated.

"That's only possible because demon souls aren't like human souls," Lydia continues. "If they have bodies at all, they don't come by them honestly – which is, in case you were wondering, how most demonic magic works at all."

"No, wait – I know some of this," Stiles interjects. "Derek explained it to me once – they wear bodies like we wear clothes, so they can step out of them and make repairs or, um, pin stuff together – okay, it's not a great metaphor, but that's part of how they shape-shift. They can even... sort of reach out of their bodies and into _our_ bodies, make us feel fear or arousal – even make us heal faster than we would on our own." How Derek's ilk were able to leave a victim without a single bruise or suspicious ache after a night of potentially _very_ energetic lovemaking had been the subject of Stiles' very reasonable curiosity since early on in their relationship. Eventually, Derek had given in and explained.

"Very good," Lydia agrees. "But the same principle also leaves them vulnerable. The right spell can untangle a demon soul from the form it inhabits and bind it to something else."

Stiles turns this over in his head. "So that makes them leave their... I guess you'd say their _living_ body and possess whatever they're bound to instead?"

"Not necessarily. A binding _can_ limit the distance between demon and artefact, but that's not traditionally the point. The _point_ is that the demon can no longer be killed by damage to its physical body – only damage to the anchoring artefact can harm them. Bind a demon soul to an object of your possession, and you quite literally hold their life in your hands."

"That... sounds like it could end badly." For all that Stiles' practical record may speak against him, even he's not so stupid he doesn't know a bad idea when he hears one.

"And it usually does," Lydia agrees, lightly. "Practical applications are varied: a demon seeking immortality might attempt to store its soul away for safekeeping – which always provides a dilemma – do you want the item close enough to keep an eye on, or so far away that it can never be found? Fragile items take souls more readily, hold less restrictively and are more easily moved and hidden, but the risks are obvious. The histories tell of demons bound to monuments or gateways as guardians, the spell functioning both to limit their movements and oblige them to protect the structure in question. But as you might imagine, more ambitious magicians have often had their own motives for binding a powerful demon soul to something convenient and easily damaged. Not as effective as what you've achieved, of course, but for many purposes it does the same job. Up to a point."

"That point being when the demon murders you in your sleep and steals its soul-item back off your body?"

Lydia gives him a thin smile. "Something along those lines. According to the histories, some magicians have been known to go one step further still, binding the demon to their _own_ body. To my understanding, the main school of thought regarding how to achieve a true will-binding – at least among those less informed than ourselves – is through a variation on the same spell. You can see the advantages, I'm sure – a demon couldn't risk harming its own worldly anchor. Unfortunately, it hasn't much cause to cleave to the will of that person either. You can't very well threaten to stab yourself in the chest if your pet won't obey."

"Okay," says Stiles. "What else?"

"And that's the theory in a nutshell," says Lydia. "Binding a demon's soul is one thing. Binding a demon's _will_ is something else. And from what I understand of the theory behind an inverted demonic thrall, the reality works by other methods entirely. Ergo: a spell to unbind a demon soul from a physical object won't be much use to you."

"Yeah," says Stiles, already thinking, "But what if some of the principles still apply? How does the thrall work exactly?"

Lydia raises her eyebrows at him. Stiles waves his hands at her. "Look, Derek's told me most of this stuff, like, _once_ , okay? Maybe if we go back over it, something we're missing will come up."

Lydia shrugs, but humours him. "It's a peculiarity of that demonic species," she begins, as if ticking off a list. "It works by a similar principle to that which allows them to arouse desire on the part of their victims, such that subjects typically report the experience as a dream-like state wherein nothing but satisfying the demon – and being themselves satisfied in turn – mattered while the thrall was in effect. The subject can, in some cases, be compelled to perform acts beyond their natural capability, such as feats of strength or the abrupt loss of consciousness on command. It puts sufficient strain on the human psyche that few, if any, subjects survive longer than seven days in that state. It can be ended either via consummation of the desire or by the death of the offending demon. Virgins are the most susceptible, though non-virgins are by no means necessarily immune, and coming out of it ranks as one of the more unpleasantly surreal experiences one could ever hope _not_ to experience in person."

Stiles winces. That last part didn't come from Lydia's books, and he's embarrassed to admit that facet of her own recent past had slipped his mind.

"Okay," he says, thinking as he speaks, "there's a lot of stuff on that list that doesn't apply to whatever hold I've got over Derek. No trance state, no virgins, no ends-with-sex, no one-week-limit, and I definitely can't make him fall asleep on command. So when they call it an 'inverted-thrall', maybe that's not so accurate. Maybe it's got more in common with traditional soul-binding than we're giving it credit for."

"Such as?" Lydia prompts.

Stiles casts for a way to back up instinct with fact. "Well, when a demon soul is bound to a human body, any harm that comes to that human, the demon feels, right?"

"That's the principle, yes."

"So, logically, they'd feel pleasure too, right? That's part of what Derek gets from me now, all the time." Excitement rising, Stiles is already having to work to keep his voice in check. "That's what incubi do whenever they touch a human – that's half the reason they're so _good_ at giving people a good time – they're feeling what _you're_ feeling the whole time! The only difference is it goes deeper – they feel what you _want_ as well as the physical stuff." And maybe Stiles is letting himself get carried away, maybe he's grasping at straws, but the idea he might be onto something is growing with every new detail that comes to him. "What if it works because the demon puts – puts a little bit of his soul into your mind, whenever you touch, until eventually it sticks there? What if a will binding _is_ just like a soul-binding, only the soul is bound somewhere different? Somewhere only the demon itself could put it?"

Several seconds of silence later, Stiles realises that either his questions have been taken as hypothetical or Lydia's still waiting to see whether he's done. "What do you think?" he asks, a little stupidly.

"I think that's a very interesting working theory, Mr. Stilinski," Lydia decides. "Coloured by wishful thinking, certainly, but for all that, not wholly implausible. I think it merits further research."

"Right," says Stiles. "Do you need me to go, again?"

" _You_ ," says Lydia, "stay here and answer my questions. My sources provide a definitive list of features and side effects characteristic of a soul-binding, and you and I are going to go through _all_ of them and figure out how many apply."

The books are under Lydia's bed, as it turns out. Presumably, that's not where they're usually kept, but it does at least mean Lydia can get to them in no time at all.

* * *

From there on in, the task gets harder.

Lydia's books can't tell them everything. By the time the candle has burned down to a nub, they're already running into things beyond the collective knowledge of the both of them. Lydia takes this on board with typical pragmatism.

"If we want our best chance of making this work – and it goes without saying that we do – we're going to want to put some of these questions," she taps their notes with her quill, "to an actual demon. Sooner rather than later."

She raises an eyebrow at Stiles, who goes suddenly cold. "Um."

"Is that a problem, Stiles? You do get around to _talking_ to one another, don't you?"

"W- _yes_ , that's not..." He gathers himself. "I don't want Derek to know we're doing this."

This gets him both eyebrows. "Stiles?"

Stiles flails a little. "Obviously if we hit a wall – if we know it's never going to work without his input – fine, sure, I'll tell him, but I think," he takes a breath. "I think we should leave that as a last resort."

"I take it," Lydia replies, after one of those pauses that go on slightly too long, "there's some very pressing reason why your demon shouldn't know you're trying to set him free?"

Stiles takes a deep breath, and says, "Because I _want_ this to work, okay – I really, really _need_ this to work. But the only way we'll know for sure that it's worked is Derek. He's the only one it affects, so he'll be the only one who knows. And as long as he's stuck with this compulsion to give me what I want..."

"You think he might lie to you, and let you think it's worked when it hasn't," Lydia finishes, seeming both impressed and suspicious that Stiles is delivering a selectively edited version of the whole truth. "One would think a newfound willingness to bed people other than you might be proof enough."

"But we couldn't be sure," Stiles insists. "And..." There are probably better answers he could give her than the truth, but none he can be sure she won't see through, or that won't find some way to backfire on him later. "I don't... necessarily want him to have to bed other people. That's not the point of this. I just want him to have the option, if that's what he wants to do _,_ " he finishes, a little lamely.

Lydia returns her quill to the inkwell and gives him another long look. "Stiles. You may have to explain for me exactly what you mean by that remark."

"I'm not trying to get rid of him. It's not just a sex thing with us anymore, I'm just – really _gone_ on Derek, okay? But none of this would have happened if he'd had a real choice about going back to me, when this all started. He _hates_ that. Can you blame him? And sometimes he blames himself, and sometimes he blames _me_ – sometimes _I_ blame me! But when I found out what was really going on and freaked out, he backed away from that to make me feel better, and now I don't know _what_ to believe!"

Forced to pause for breath, only with some effort does Stiles remind himself that not only is none of this Lydia's fault, he's edging into territory that goes way beyond what she needs to know. He's not sure he can quite remember what the original question even was anymore. "He wants me to believe that if he had a choice to make, he'd choose me. If that's true, this'll be his chance to do it, and we can both stop wondering," he finishes, and shuts his mouth before Lydia's pointed silence can goad him into tying himself into any further knots.

"And if he chooses otherwise?" Lydia asks, having apparently elected to ignore the rest of his little outburst.

"Then he chooses otherwise." He shrugs, though it's probably not convincing. "I can deal."

The look on Lydia's face tells him it's nowhere _close_ to convincing. "So, in summary, you and I are attempting to overthrow centuries of magical doctrine on the back of little experience at no small personal risk for what, if all goes well, will amount to a very nice _gesture of good faith_ from you to your demon lover?"

"Yes," says Stiles, "No. I... I know this might not work. I know it might not work out even if it does. I just need to be the guy who _tried,_ okay?"

Lydia sighs through her nose. "Alright. So Derek's out of the picture. Lucky for us there's other options available." Before Stiles has had the time to catch up with what she's said at all, Lydia's already saying, "Erica: my room, if you please?"

"What?" says Stiles. "You – _what_?"

He's still staring at her in disbelief when Erica appears in the doorway. "M'lady?"

Stiles stares at her, then back at Lydia. "You _know?_ "

Lydia rolls her eyes. "Oh, _please_. _One_ demon in my room unannounced is too many. Would I risk letting another demon into my room without knowing about it?"

Erica shrugs at him, barely sheepish. "Sorry. Would've brought it up, but you seemed to have enough on your mind." She turns back to Lydia. "Was that all?"

"Actually, no," Lydia replies. "Stiles? Perhaps you'd like to explain."

Stiles thinks frantically, but he doesn't _think_ there's a good reason why they'd have to keep this from Erica. "We think we might be able to find a way to undo the binding between Derek and me," he tells Erica. "But we could use some input from – the other side, and I don't want him to know about it yet."

Erica breaks into a grin. "I knew there was a reason I liked you so much," she declares. Sauntering into the room, she makes herself comfortable on the bed. "What can I do for you?" she asks them, and proceeds to be very helpful indeed.

It's a little later that night that Lydia tugs Stiles aside. "You realise, of course, we're still going to need a physical token of Derek's to make this work."

Stiles nods back – he hadn't thought that far exactly, but obviously they're going to need something to give the spell a target. "You mean blood?"

"He's an _incubus_ , and we're trying to free him from a very specific magical binding, unique to his species," Lydia pronounces, her emphasis quite deliberate. "I think I can say with very little doubt that we're going to need _semen_."

"Well," says Stiles. "That. Shouldn't be a problem."

It isn't.

* * *

Nested in the recesses of his mind, Stiles actually has a _lot_ of complicated, overlapping reasons for keeping what they're doing from Derek. Among those he hadn't admitted to Lydia is that he kind of wants to test whether keeping something this big from Derek is possible at all. It's not even just about the magic stuff, or about how much Derek can read from his mind now the connection has had this long to solidify. It's just as much about whether _Stiles_ can avoid giving it away.

He hasn't decided exactly what it'll mean if he can, or if he can't. _Should_ his privacy trump Derek's right to one of few advantages he might have left? He's not even sure which one he'd rather be true, if he had that choice. According to Derek, Stiles has the power tokeep things from him, but everything Derek says that Stiles wants to hear is suspect now. And the only way to know for sure is to have a secret big enough that Derek can't easily pretend ignorance if he knows.

Stiles isn't going to get a lot of opportunities that fit that bill.

As his werewolf best friend will gladly testify, Stiles can keep a secret with the best of them. But keeping something that already has him conflicted from someone he really cares about is a whole different thing. Derek's not stupid; there's no way he's unaware of the new vein of tension open between the two of them nowadays – but realistically speaking, it's not like Stiles is short on other good excuses for that.

"It's still bothering you, isn't it?" Derek asks, fingers light across the ridges of Stiles' spine, breath as he speaks an even lighter gust against his skin. Derek's not talking about keeping secrets, or what Stiles is doing with Lydia. He's not wrong, either.

"I don't think it would say good things about me as a person if it wasn't still bothering me," says Stiles, because it's true. He rolls over to face Derek properly. "It still bothers _you_ , doesn't it?"

"Less than it did," Derek admits. "Less than I thought it was going to, before you knew. I think it would bother me more if it bothered you less." His fingers fall to Stiles' hip, never still for long, cataloguing Stiles' skin by inches, soothing and comfortable even as the topic of conversation becomes anything but.

"Then you get where I'm coming from." This comes out more bitter than Stiles had entirely meant it to.

"Stiles, I know this isn't what you wanted." Derek's voice is soft. "But it's the only thing I can have."

_It shouldn't be_ , thinks Stiles, but it's the objection of a child and he knows it.

For all the progress he and Lydia have made, they still don't know for sure whether what they've been piecing together from part of this spell and that theory will ever add up to something that works. _This_ might be all he and Derek can ever have. There's a look in Derek's eyes lately – something that's infested his whole demeanour – like the possibility of losing Stiles has settled into his subconscious, and is there in the subtext of everything they do. The possibility he'd admitted to when he'd come back to apologise – the fear that Stiles might do what he couldn't and send him away – doesn't seem to have faded with their new understanding. Stiles hates that so much he wishes he'd never noticed at all.

"I guess I'm still trying to get my head around it," he admits eventually, a peace offering of sorts.

"That's fair," says Derek. "I haven't always been as forthcoming as I might."

"So if I had more questions..." That's hypothetical: Stiles will alwayshave more questions. Ironic that lately he's been _less_ inclined to push, now that he knows he could almost certainly get Derek to answer anything.

"Ask them." No hesitation whatsoever.

Stiles thinks hard about all the ways to put his worst insecurities about what he could do to Derek into words. He thinks about all the facets of how this works that he and Lydia are still struggling to understand.

What he asks is, "So who's Laura? "

The movement of Derek's eyes is sharp, surprised. Stiles shrugs, apologetic. "Erica and Isaac mentioned her to Scott and then clammed up suspiciously. Scott told me. That's as much as I know."

Derek rolls onto his back, facing the ceiling. "Laura was my mentor. Theirs too, when we were all younger."

" _Was_ ," Stiles notes. Past tense. "She was a succubus?" Derek nods, eyes distant. "What happened to her?"

"She was the rogue's first victim."

Stiles feels his eyes widen. Whatever he'd imagined, this is... But then, why hadn't he? The pieces are falling into place in his head before Derek's even begun to explain.

"We were separated at the time. I didn't see it happen, but other demonic presences make an impression in our minds. Stronger by age and power, but strongest for those we've been close to. Laura could've been oceans away, and I would have known." Derek takes a breath, short and louder than those that came before it "She was ambushed. It was over fast. The last thing she felt..."

"A strong demonic presence you didn't recognise," Stiles guesses, if you can call it a guess. "I'm sorry."

"I was trying to forget," Derek admits.

Stiles still remembers the rage in Derek's voice when he'd spoken of the incubus who'd attacked Lydia, but it had been fleeting, and gone. He'd had no idea Derek was mourning the death of family. But maybe it doesn't hurt to be reminded that he's not Derek's whole world. Derek's world is bigger than him, even now, and so much bigger than he knows.

"So when you said you were after the rogue because he was revealing himself to humans..." It's too long since the fact for Stiles to recall Derek's exact wording, whether he was guilty of lying outright or lying only by omission – but then, he'd never owed Stiles the whole truth anyway.

"If that was all he'd done it would've been enough. Not as personal, but enough."

Stiles believes him.

"I'm sorry," he offers – and as a sentiment it's too late, too little, and too obvious to be worth more than any other rote condolence, but there's some relief in knowing that Derek almost certainly _will_ understand what Stiles wants him to know, but doesn't quite know how to say.

Derek nods quietly back. It's a little while before he rolls over again, drapes an arm across Stiles' body and pulls him into his space.

Maybe he'll tell Allison about Laura later. He doesn't think Derek would mind. Maybe he'll even tell her about Lydia – at least enough to let her know even Lydia doesn't deny that her mother really did have a history of doing business with demons of a class that (by Lydia's own account) sound very much like Derek's ilk. It's by no means unthinkable that an enemy of their kin might have had a score to settle with Lady Martin, too – to hear Lydia speak of her mother's work, she's spent her life half-expecting some angry demon to appear on her windowsill any day. But there's no part of that they can safely tell the other hunters; no way to frame it that would make Lydia any less guilty – by association if not deed, by intent if not by act.

She's as guilty of being a witch as Scott is of being a werewolf; as Derek and Erica and Isaac and Boyd are of being less than human. None of them get that easy an escape when the hunters are on their trail.

* * *

It's on his third day of surreptitious visits to Lydia's room that Stiles runs into Jackson in the doorway – very nearly literally, and without any sort of good excuse for what he's doing up here prepared. There's a wealth of meaning in the glare Jackson shoots at him before shouldering his way past – or there certainly would be, if Stiles had the first idea how to translate Jackson-to-English. He's still stuttering uselessly through some non-excuse about something Lydia might conceivably have wanted him for to Jackson's retreating back when it registers that Jackson _hasn't asked_.

"Does he _know_ what we're doing here?" is the first thing he says to Lydia when he gets through the door – and at a volume certainly louder than is wise, considering Jackson can't have made it past the stairwell.

Lydia pauses in retrieving their notes to look at him. "Does Jackson know we're attempting illegal dark magic in order to free you from your unspeakable bond with the demon you've been welcoming into your bed since the night I almost died?" The sarcasm oozes from her (pointedly softer) voice.

"Is that a 'no?'" asks Stiles.

"Don't worry about Jackson," says Lydia. "We have an understanding."

"Is _that_ what you're calling it?" The words are out before Stiles can think better of them.

Lydia does not glare at him. She does not give him a look. She takes a casual interest in the far wall, and leaves Stiles to reflect for himself on how very much this is not his business, how _very_ little ground he has from which to question who _she_ might choose to sleep with, and perhaps to speculate as to exactly how much he really wants to know about her relationship with Jackson anyway.

Stiles casts helplessly for a safer topic. What he arrives on doesn't entirely fit the bill. "You know... before the fair, Kate was trying to get him to spy on you. She had him thinking you were a witch. I told him that was crazy." The retrospective irony isn't lost on him. The real risk of Jackson blowing to pieces if he _does_ discover now that Kate had been maybe-a-little-bit-right all along isn't lost on him either. "I also told him Kate was just messing with him," he adds, in his own defence.

"Good of you," says Lydia.

Stiles has spent at least ten seconds trying to make up his mind how to phrase the question when Lydia rolls her eyes. "No, Stiles, I don't need you to warn me. I know the hunters are watching me. I know they've tried to get to me through Jackson – and Allison, and Harris, and Rebecca, and every other person to spend more than an hour in my company since I was barely a dozen summers of age."

"And... Jackson?"

"Doesn't need any new reasons to distrust Kate Argent," says Lydia, firmly.

Stiles badly wants to ask, _Can I at least know what you told him so I can keep my story straight?_ but Lydia's so clearly telegraphing that the answer to that is going to be _no_ that even Stiles, for once, eventually settles on the wisdom of keeping his mouth shut.

* * *

By the time they've had Erica on board for more than a couple of days, Stiles has had plenty of time to come to appreciate that the best thing about the arrangement might well be the part where her supernatural hearing allows her to warn them well in advance when they're about to have company.

"Advance warning:" announces Erica, "Kate's on her way upstairs."

This is not the first time Kate's dropped in unexpected today. It's not likely to be the last either. She's been executing regular spot-checks for forbidden magical acts in progress under a variety of thin excuses on a distressingly regular basis.

Doesn't especially help that that's exactly what they have actually been doing in here with every free hour the three of them can find.

Books and notes can be shoved away and hidden with haste if they need to be, and Erica has ample excuse to be found in Lydia's bedroom at all hours of the day – but Stiles isn't so easily hidden or explained away, and there's only one flight of stairs. Very soon they're going to need an excuse that'll last through more uses than those they've relied upon so far.

"No pressure, but we're about to need a much better reason for me to be up here," Stiles tells the others. "She's not going to buy the coincidence line forever. Lydia never has _this_ many jobs for me."

"Maybe she doesn't," says Erica, with a glint in her eye. "But it's not _Lydia_ you're up here to see, is it?"

This is how Stiles finds himself pinned between the wall of a convenient alcove and Erica's very... _Erica_ cleavage, playing the "just two servants canoodling in the corridor" gambit for all they're collectively worth.

On the one hand, the months Stiles has spent bedding a demon of masculine persuasion do not mean he's no longer attracted to girls, or that he's immune to the incredible aura of _do me_ that Erica exudes.

On the other, the fact Derek quite plainly gave him _clear permission_ to experiment elsewhere, that doesn't mean Stiles feels totally okay about taking advantage of that, not least because _Derek_ doesn't get that freedom, and not _least_ with what amounts to Derek's little sister. (Does bedding an incubus _not_ make you immune to the thrall of a succubus? He should really ask Derek sometime. Sometime far into the future when doing so no longer feels incriminating.)

"You _can_ touch, you know," Erica whispers. "Make it look good."

"Derek is _not_ going to like this!" Stiles hisses back.

"He'll understand," says Erica, and kisses him full on the lips just as Kate reaches the top of the stairs.

The level of privacy offered by the alcove is... well, "private" is certainly not the best operative word. That said, Stiles privately feels that there's nowhere they could have done this on this entire floor that Kate wouldn't have zeroed in on from wherever she stood.

The sound Kate makes is _not_ surprised. "Approving" is probably much closer to being the adjective it deserves. It's also loud enough – deliberately, if Stiles is any judge – that they can't well not look up and 'notice' that she's there. Stiles takes some small solace in knowing that the look on his face is surely guilty enough to be entirely convincing.

"Oh, don't let me interrupt," Kate croons.

Erica grins slyly back and takes the invitation.

A small eternity seems to go by in the time it takes for Kate's footsteps to finally retreat around the corner into Lydia's room. Stiles explains to Erica in no uncertain terms that they're not going to still be there when Kate comes back out again.

* * *

Stiles hasn't so much as gotten around to telling Scott what he and Lydia are up to yet, and it doesn't really occur to him that he maybe should have until Scott starts asking awkward questions about what's going on with him and Erica, and whether he's still with Derek, all the while looking tremendously uncomfortable about having to ask anything of the sort.

Considering how precious little there is to do for fun around the Tower nowadays _except_ gossip, Stiles eventually has to face the fact he's got no-one else to blame for not having seen this one coming from the moment he and Erica stepped out of Lydia's room. He blames Kate anyway, just on principle.

* * *

Lydia draws a circle on her floor and works a ritual that will bind Erica's soul to a gold bracelet, laid carefully at the centre of the diagram, dark with demon-blood. (Lydia stresses the fact she's never actually attempted anything of the sort before, and can't promise it will go exactly as planned. Naturally, she makes it work first try.) Stiles gets the privilege of watching as Erica plunges a dagger into her own chest, then pulls it out again without flinching, the wound healing over almost instantaneously. He only gibbers a little.

They send Erica on a long night-flight, as far as she can comfortably go, and interrogate her on her return about the sensation of being separated from her own soul (by her account, not strictly painful, but not pleasant either, worsening with distance) – with particular attention to any points of similarity with her earlier reckless experiments in going back to the same human bedmate once more than traditionally recommended. When they're done, Lydia steps into the circle with the bracelet on her wrist, and transfers Erica's soul to her own human body. She pricks a finger and watches Erica twitch, then they send their test subject out again for another flight, then another round of questions.

They read everything Lydia's books can tell them on the subject of the thrall, on the precise definitions of 'magical virginity' and everything that can increase or decrease susceptibility, and then quiz Erica for more. Stiles runs out of ink for his notes and has to go beg for more from Boyd.

When he gets back, he walks in on Erica casually suggesting that they might provide themselves an even _better_ source of comparison were she to invite herself into Lydia's bed once or twice – all in the name of logical enquiry, of course – if only she weren't bound by "a prior agreement" on the matter. Lydia tells her that shouldn't be necessary, though she looks far more intrigued than Stiles is entirely comfortable with.

Small wonder people tell you dabbling in this stuff is bad for the soul.

* * *

Stiles' hasn't spent his years of instruction entirely deaf to Deaton's warnings, no matter what the last few months might imply about the matter. He knows experimental magic is dangerous territory; experimental _demonic_ magic is what cautionary tales are made of – or would be, if your average parent would ever dare tell that sort of tale where impressionable children might hear. Lydia's books, supplemented by her ancestors' notes, supply them with page after page of dire warnings about the consequences of failure, the details ranging from disturbingly specific to worryingly vague. There's considerable solace in knowing that Derek's not _actually_ likely to tear them both limb from limb if the spell fails, which whittles the main class of danger down considerably, but the same factor leaves Stiles painfully aware that this is Derek's _soul_ they're going to be messing with. If it's theoretically possible to undo a will-binding at all, then it might be theoretically just as possible to get this wrong and unbind the wrong anchor altogether, to say _nothing_ of any of the more traditional classes of failure the books describe, or allude to, or record in uneven hands in the margins of the spells at fault.

If they're going to do this, they need to be very, very sure they've got it right.

Eventually, Lydia closes a book on Stiles' fingers and, once the jumping up and down and yelping has mostly stopped, declares, "We're done here."

"Wha...?" Stiles protests. "But we still..."

"We have a complete working theory of what the ritual ought to require that we haven't substantially modified in two days of work. We've been over every relevant page of every book we've got _twice_ since we started. And we have less than two days left before the hunters are due back. We're done. You're doing this _tonight_ , so we still have time to clean up if fails in some particularly messy fashion."

Stiles looks helplessly at Erica for support.

"What's the matter, Stiles? Cold feet?" says Erica.

Stiles swallows and gives in.

* * *

Lydia suggests that the room he and Derek have had the most sex in is probably going to be the best place to work his magic, then passes him the relevant supplies and makes it abundantly clear that she intends to spend the duration of the event guaranteeing herself an impeccable alibi.

Stiles lights himself some candles, explains to Scott that he needs the room to himself for a while (and a heads-up if anyone's coming) for unspecified Derek-related reasons, and then...

The magic isn't actually the hard part. The magic, Stiles can do. He can draw diagrams. He can inscribe runes. He can place tokens and string thread between the points of a pentagram. At the end of the day, it's all symbolism – the language the magician uses to focus the mind on what needs to be done. He can make himself _believe_ this is going to work – at least for the duration of those crucial moments separating doubt from realisation. He can feel _something_ go ricocheting away when he slices through the thread.

He thinks he can, anyway. The doubt – or at least, the worst part of the doubt – comes _after_ , once it's all done there's no more he can do but cross his legs and wait to find out whether it worked.

Stiles sits on his bed, shuts his eyes, and _wants_ Derek to appear, and waits to see whether it doesn't work.

* * *

It's hardly two minutes before Stiles hears motion at the window.

Two minutes is more than time enough to work himself into such a state with anticipation that it would have taken him a minute to remember whether this result is the good one or the bad one, or just meaningless coincidence. None of that matters though, because before he's had time to be disappointed, or relieved, or any other meaningful response, Derek's in through the window and crossing the floor in the candlelight and-

The first real sign he gets as to whether the spell worked or failed is that Derek looks _haunted_.

"Stiles?" In hardly more than two paces he's crossed the distance from the window, brought a hand to Stiles' neck – somewhere in that space Stiles must have stood up to meet him, because Derek has him backed all the way up against the wall before he knows what's happening or how – just that only once Derek's touching him does the greater part of the tension slump out of Derek's face.

"Stiles, what happened?" Derek asks, hands taut against Stiles' frame like he's afraid to let go. "I couldn't feel you. All of a sudden you disappeared."

"Oh my god," breathes Stiles, because it's suddenly so obvious – of _course_ Derek would come running! "It worked!"

Derek's hands fall from his skin. He looks at them, then at Stiles, takes one step back, and looks down and up again. "Stiles," he says, suddenly guarded in a way Stiles has never seen him before, "What did you do?"

If Derek's not ready to celebrate yet, Stiles will do it for him. "You're not bound to me anymore! I broke it. It's not unbreakable! We found a way to do it – me and Lydia, I mean – turns out her mother really _was_ a witch, and she knows so much more about this stuff than maybe even Deatonknows." Lydia is going to be _so smug_ when he tells her how this went, and she'll have more than earned it. They haven't just pulled off a little risky magic, they've done real magic no-one's _ever_ done before! Stiles feels positively giddy with success. "Oh, and, uh, sorry I never told you what we were doing, but we kind of needed you _not_ to be expecting it so we could know for sure if it worked. And it seemed so crazy to begin with I kind of didn't want to get your hopes up about it. But it worked! Oh my god, how amazing is this?"

It's no great surprise to note that Derek doesn't look like he's entirely understood. Stiles is aware he's not at his most eloquent when he's excited. "Look, I know this sounds nuts – you thought it was impossible, and even _Allison's_ never heard of anyone breaking a will-binding before, and I'm a complete beginner, and Lydia's good but even she's hardly practiced much before. I mean, even Boyd and Isaac were saying no-one's ever bound a demon to their will by accident before, but that's why I figured: what if the only reason people think it's impossible is because no-one's ever been in a position to try?"

" _Stiles_ ," says Derek at last, stopping him before he can get carried away. "I need to check if I have this straight. You and Lydia invented a spell to break the binding between us... just to see if you could?"

"Well, not _just_ to see if we could." In Stiles' head, the reasons for wanting it broken are at once so simple and so tangled up in layer on layer of 'but _also_ because...' that, out loud, it's hard to know where to start. " _Yes_ , I wanted it broken. I mean, you were never happy about it, and you sure noticed _I_ was never thrilled about being on the hunters-most-wanted list, to say nothing about the whole 'your life at my command' thing – you've got to know that was never what I wanted out of a relationship."

Derek swallows, throat working silently under Stiles' gaze. "So this means... it's gone for good?"

"Well, it'd probably come back if we slept together some more, but it's not going to just wear off or anything," Stiles assures him.

Derek just looks stunned now, his face open in a way that's strange and unfamiliar, which presumably means the reality of the situation is starting to sink in. "Stiles," he says, voice eerily flat. "Do you... want me gone?"

"What?!" How could Derek even think that? Except... Stiles runs back over the conversation thus far in his head with new eyes. Possibly he could've made his intentions here a little more obvious a little sooner. "No! I don't _want_ you to leave. I just want you to be able to leave if _you_ want to!"

Derek frowns at him. "You thought _I_ wanted to leave?"

"I thought you mightif you got the chance to! C'mon, Derek, we both know this was an accident, that you'd never have let this happen if you'd been thinking clearly. You _told_ me that!"

"I told you that because I was angry. I apologised."

"And that was very sweet of you, but how far am I supposed to believe it when you were being coerced to do whatever I want, and that was just what I wanted to hear? This is the only way either of us could ever know for sure." _And it was the right thing to do. Isn't it?_ Stiles is about to add, but stops himself, second-guessing how much something so self-evident is going to help.

Derek takes a moment to reply. Never in all their association has Stiles seen him look this unsure, and he's not sure he likes it. "What do you want me to do, Stiles?" he asks at last.

Stiles spreads his hands. "I want you to do whatever you want to do! That's the whole point!"

"No," says Derek, slightly impatient now – which is at least more familiar territory. "I'm asking what _you_ want me to do."

"Don't you know?" says Stiles, because up until three minutes ago Derek knew what he wanted before he wanted it himself – he _can't_ have missed something this big. But maybe he needs to hear it out loud? "I want you to stay. Even if we have to end up bound up again, I guess that's okay. But you don't have to. If you don't want to." Stiles breathes out and makes a concerted effort to gather himself; all this awkward sincerity is making him miss the mind-reading parts of the relationship. "That's sort of been the whole point of this, if that's not getting through."

Derek blinks at him.

"Do you... want to stay? With me?" Stiles prompts.

Derek blinks at him again, then turns his eyes downwards, and it's only when Stiles notices his shoulders are shaking that he realises Derek might be _laughing_ at him. But before he can protest, Derek's looking back up at him, and the smile on his lips has settled into something positively sinister.

"Stiles," says Derek, crowding his way into Stiles' space, "You performed dangerous black magic. You talked a young lady of noble blood into following her disgraced mother's footsteps." Running his hands down Stiles' arms, Derek pulls both his hands over his head and pins them there. "You did it all under the noses of the Argents – of hunters who'd have your head for even _thinking_ the half of what you did. And you did all that for me." Derek's mouth dips from Stiles' ear and finds his neck with proprietary interest, and – _oh,_ that's his answer, isn't it? "And you think, after all that, I might _give you up_?"

It's the raw disbelief in his last question that does it. For a little while after that Stiles is so caught up in being so stupidly happy, with kissing Derek (or mostly being kissed _by_ Derek) like it's all new again, that he almost doesn't remember that there's more to how this is supposed to go. "Wait, wait!"

Derek ducks back and lifts an eyebrows, watching Stiles like he's humouring him. He doesn't release Stiles' hands. It's only now that he's started to look every bit as insanely joyful about this as Stiles himself, and the looks works for him in unhelpfully distracting ways.

"Think it over for a few days first?" Stiles tries.

"A few days?" echoes Derek.

"You're all caught up in the celebrations now! The bond's been gone for, what, five minutes? This could all look different the day after tomorrow?"

"You think I need a cooling off period?" says Derek, in open disbelief.

"It sort of defeats the point if you don't?" The point here would probably be coming through much clearer if Stiles' arguments could only stop coming out as questions. "You haven't had any time to really think about whether you want to be with me since... since probably never! So, you know, take a few days. Go... fly around a bit! Go somewhere you can't make it back here in ten minutes from! Maybe even..."

"Bed someone else?" Derek finishes for him, voice pitched low. "Is that what you want me to do?"

Stiles shrugs, helplessly – he _doesn't_ ,honestly, but that's not the point. Except for how it kind of _is_ the point. "I just want to know you're sure."

Derek lets go of his hands. He steps back. "How long?"

"Huh?"

"How long is 'a few days?'"

"Um," Stiles, naturally, has not thought this far. Every possible duration he falls upon seems either far too little or far too much. "A week? How about a week?"

"Alright," says Derek. "A week." The hint that he's being humoured is subtle enough that Stiles has to turn the words over in his head a couple of times before he gets it – before it starts to sink in that Derek may very well take _eight_ days just to make him worry a little. That Derek may be agreeing, but what he's _thinking_ is more along the lines of 'pleasure delayed is pleasure magnified'. Only somehow dirtier.

"Alright," says Derek. "Until next week, then." Everything in his voice is a promise.

With that, he turns on his heel, and barely stops in the window to give Stiles one last, knowing smile before he's gone.

Stiles slumps against the wall and smiles like a love-sick fool until his cheeks ache from it.

* * *

Because the spell worked there's very little mess left afterwards to be cleaned up or hidden away. At the end of their marathon of magical study, Stiles has a whole day remaining to achieve that little. When the hunters do get back, they do so a day late, and then at an advanced hour, taking supper apart in their quarters that night.

In all, Stiles gets three whole days and part of a fourth beyond in which he can, perhaps foolishly, almost believe that the worst is over, and that everything left from here might really be all right.


	13. Chapter 13

"Message from Allison," Scott tells Stiles the morning after the hunters' return. "She needs to talk to you about something they found on their trip."

That Scott has found the opportunity to speak to Allison despite the hunters more-or-less locking themselves in their chambers last night isn't very surprising. That Scott felt the need to let _Stiles_ knowabout it, however (and isn't that just a whole other conversation about the relative necessity of oversharing that they haven't had to revisit in months), suggests the message is pretty urgent. She and Stiles live in the same building, ferchrissakes, it's not as though Scott's her only means of getting his attention. "Did she say what kind of something?"

Scott glances nervously back over his shoulder. "She said they found a demon skull," he whispers.

"Found? Found as in 'found in the newly-dismembered body of its owner' or found as in 'that's all there was left to find'-found?" Stiles reminds himself it has been _three days_ since he last saw Derek. Even _Derek_ would have to outdo himself to manage to get 'found' by the hunters that quickly.

"'Found' as in 'it was dead for a while before they got to it'," says Scott. "It came from somewhere way out east of here, something to do with another clan of hunters they were looking for. That's all she said."

Stiles considers the plausibility that the death of some unknown demon some unknown distance away represents the stuff of ordinary coincidence, of no great concern to themselves. It's not impossible, but they're definitely not odds he'd bet his life on. Stiles would gladly trust Jackson further than he would his own luck of late, depressing as that sentiment may be. "Did she say how far away it was?"

"I don't know," says Scott, sounding gloomy, "you'd have to ask her,"

"Did the other hunters kill it? How long ago? Days? Months? _Years_?"

"I don't know that either."

"Was it an incubus or a succubus or some other demon altogether?"

"I think one or the other, I don't know! You'd have to ask Allison, that's all she told me!"

Stiles resolves to do so at the very first opportunity, so of course he doesn't get one all day.

* * *

It's closer to midday when Isaac finds him. "Message from Derek."

Stiles sits up guiltily and looks around, but they seem to be alone, and if Isaac hasn't yet drawn attention to having caught Stiles napping in the sun behind the woodpile, he's sure not going to raise the subject himself. He clears his throat. "What, have you seen him? Is he here?"

"Not that kind of message," says Isaac, and taps his head, meaningfully.

 _Oh_ , right. Nice of Derek to have given him the heads up this is something he and his pals can _do_ , at least, but the timing is giving Stiles a bad case of déjà vu. "Does it involve a missing demon skull by any chance?"

Isaac's face scrunches with confusion. "How did you know that?"

"Lucky guess." Stiles sighs, brushing off his legs as he pushes to his feet. "The hunters have it. Or so I hear. Is it important?"

"Why would the hunters have it?" asks Isaac. "I thought they burned and buried the body."

"I don't know; I don't even know where it came from yet!"

Isaac looks only more confused. "Weren't you here when they killed it?"

The nagging suspicion this conversation has gotten off on entirely the wrong foot settles on Stiles with the promise that the day's headaches have hardly even begun. "Alright, I'm starting to think we may be talking about different things. How about you tell me Derek's actual message from the start?"

Isaac nods. "He needs us to find the skull of the rogue – the one he killed back when you and he met. He's on his way back for it."

Stiles stares at him. "Did he say why?"

"Not exactly," says Isaac, looking suddenly cagey.

"But you've got a pretty good guess anyway, huh?" Stiles hazards.

"Maybe?" says Isaac, "I'm not sure if... what's this story with the hunters, anyway?"

If Isaac thinks that little subject change is going to slip right by Stiles he's got another thing coming, but it can wait. "Story is the hunters brought a demon skull home. Don't know whose, don't know why, don't know where from – when I do you'll be the first to know." Stiles shrugs and slaps Isaac on the back "So Derek wants a demon skull? Fine, we'll get that one pinned down while we're waiting. They buried it down the hill, I'll show you where. Go get Scott or Erica. Shovels, too."

* * *

Because nature has no good sense of melodrama, there's _grass_ growing on the spot where the hunters had dumped the rogue's blackened bones and unceremoniously covered them in dirt. There's even a flower or two. By the time Scott and Isaac are done digging it up, though, there's not much left of the foliage.

There's no skull either.

"You think maybe... an animal could've dug it up and took it?" Scott suggests, but it's a laughably weak attempt to come up with an innocent explanation, and he knows it.

"Why?" asks Stiles. "There wasn't even any meat left on it! Don't animals refuse to eat demon-flesh anyway?" This last is directed at Isaac, who ignores him in favour of finishing one more slow circuit of the site, grimly prodding the ground with his spade.

"So... someone took it?" says Scott, looking more uncomfortable by the moment.

"If they did, it wasn't recent," Isaac puts in. "No-one's disturbed this place in months."

The grass does provide a pretty solid testament to that.

"Alright," says Stiles, "but _why_? What good is a burnt-out incubus skull to _anyone_?"

"Maybe boasting rights?" Scott tries. "You could convince people you were the one that killed it?"

"Sure," says Stiles, who is rapidly losing patience with this whole damn day, "but I'm guessing that's not why Derek wanted it. Is it?" He looks at Isaac, who comes to an awkward stop under his gaze and shuffles his feet a little.

"Derek really didn't explain why he wanted it..." Isaac begins.

" _But_?" prompts Stiles.

"But I've heard there's supposed to be something you can do if you look into the eyes of a dead demon," says Isaac. "They say it shows you the last thing it saw before it died."

Well that's officially creepy, if not greatly illuminating. "What good is that to Derek? He _knows_ the last thing it saw before it died – he was there! The last thing it saw was probably _him_!"

Isaac shrugs. "Like I said, he didn't say. I'm only guessing."

"What if it wasn't about getting the skull," Scott says suddenly, "what if the point was to make sure someone else _didn't_ get hold of it? If the hunters found out about this – if _they_ looked into it..."

Isaac only shakes his head. "It doesn't work for just anyone. You have to know who it was before they died."

"So what good is that to the hunters? And why would they hide it in a box for months, then _pretend_ to bring it back from somewhere else?" Stiles turns back to Isaac helplessly. "Can't you ask Derek?"

Isaac shifts again and looks a little apologetic. "It's not exactly an easy way to have long conversations."

Of course not. That would be far too convenient. Not to mention actually _useful_. Stiles slumps down and rests his elbows on his knees. "So, this demon-skull the hunters 'brought back' with them may have come from closer to home."

Scott nods and stares into the middle distance. "We really need to talk to Allison."

He's right, unfortunately; there's not much else to do.

* * *

"I talked to Allison," Scott tells him, tugging Stiles into a spare room shortly before dinner. It takes a lot to leave Scott panting nowadays, but if he'd still been human, he'd almost certainly have been panting now – he clearly got here in a hurry. "I only got a few seconds before her father came back, but I asked her."

"And?" hisses Stiles.

"She's _very sure_ the skull didn't come from here."

"How sure is that?"

"They got it from some other hunters _miles_ from here!"

Stiles stares at Scott in open-mouthed betrayal. This is so unfair. Can't they even be allowed to nurse _one_ halfway-plausible theory for a lousy couple of hours without reality stepping in to dash it to bits? "Well, do they know where those hunters got it from? Maybe _they're_ the ones who took it from here!"

"Why would they do that? Stiles, that doesn't even make sense!"

"None of this makes sense! Come on, Scott, an incubus skull goes missing here one day, and the hunters just show up with another at the same time? What sort of coincidence is that?"

"Stiles," says Scott, "the hunters have had that skull for over a week, that's how long it took them just to get back here! And the one we were looking for has probably been gone for _months_! Why does Derek suddenly want it now? Where is Derek, anyway?"

"I don't know, he went off somewhere to..." Stiles waves his hands vaguely. He doesn't know where Derek is, that's kind of the point of the exercise. "Did she say anything else about where it came from?"

"Not really," says Scott, and frowns. "But I don't think the hunters they got it from were the ones that killed it. They just found it, or something." When Stiles doesn't immediately reply, his frown deepens. "You have this look like you just thought of something."

Stiles pinches the bridge of his nose and stifles a sigh. "Yeah. Maybe. We have to go talk to Isaac again. Or someone. One of them."

Sending Derek away for a week has never before felt like such a mistake.

* * *

'One of them' winds up being Erica, who, having not already had to squeeze a surreptitious grave robbing expedition into her day, is less busy than some people.

"Okay," Stiles begins, "did you get the message from Derek too, or was it just Isaac?"

"Isaac got a message from Derek?" Erica looks from him to Scott and back again. "He didn't tell me."

"Technically it was for _me_ ," says Stiles, "only... you know what, it doesn't even matter. I need to ask if you know what happened to Laura's body."

Erica starts at the name. "Laura?"

"Derek told me about her. Scott, Laura was a succubus friend of Derek's, like Erica. The rogue incubus that attacked Lydia killed her before it got to us. That's where Derek picked up its trail. What I don't know is what happened to whatever was left of Laura after that." Stiles looks to Erica, who sighs and starts to speak.

"Derek didn't say much about it. We didn't even see him properly again until right before the fair, remember? But he would have been more concerned about catching her killer than burying her body, if that's what you're asking."

"But... didn't any of the rest of you ever go back to find her?" asks Scott.

"The rest of us had a cart full of goods to move and Boyd can't fly. Besides, Derek was the only one who really knew where Laura went when she was away. He was always much closer to her than the rest of us."

"But wouldn't Derek have gone back for her later?" asks Stiles, with the sinking feeling he might finally be on the right track.

"I don't think he's been more than a day's flight away from here since he met you," says Erica. "I don't know the exact spot, but it would've been a couple of days flight away from here at least."

It's Stiles' turn to sigh. "Well he's more than a day away from me now."

"You think he went to find Laura's body?" asks Scott.

"Yeah," agrees Stiles. "Only I think the hunters might have found her first."

* * *

Having made themselves unusually scarce for most of the day, the hunters finally make an appearance at dinner, arriving late enough that everyone else is there to see them arrive. With the Argents at the head, their entire procession sweeps into the hall as if expecting some sort of fanfare. The last time Stiles saw anyone make such a show of simply arriving at dinner, Lord Martin was still at the head of the table with Lady Martin at his side, and their guests were a respected order of knights who'd come all the way from the capital to take part in the autumn joust. Nowadays, the Tower's upper ranks are more in the habit of drifting into the hall in ones and twos as convenience suits them – there's no possible way to pass this off as an accident. Stiles can't help but wonder what the point is supposed to be.

Lydia does not seem much impressed. "Mr Argent and company, so good of you to join us this fine evening," she greets them, her manners somewhat at odds with her studiously bored expression. "What news from afar? Dare I inquire as to the success of your recent endeavour in the field?"

The faint and useless urge to duck for cover twitches rapidly up Stiles' spine. This is going to get ugly.

"Miss Martin." The deferential nod Chris performs here is so slight it may not have happened at all. "I am sure our absence has been keenly felt. Far be it from me to presume to bore you with a full tale of a long and galling hunt, but I do assure you, my lady, we do not return home empty-handed."

Chris is already moving to his seat by the time he finishes, but he nods to someone in the procession of hunters fanning out behind him, and two men step forward, one bearing a wide metal tray, the other pulling away the scarf covering its contents to reveal...

Stiles twigs to what he's about to see perhaps a fraction of a moment before the blackened shape of the demon skull emerges. Even with Allison's warning, it never occurred to him _this_ might be the gambit the hunters would use. He looks for Allison automatically, but she's standing with the hunters, her expression grim and her eyes turned elsewhere, as her duty demands.

For a long moment, Lydia seems to go very still. It's been some months since Stiles has had cause to remember the look in her eyes when she'd first gazed upon the remains of the rogue incubus that morning in the snow, but something of it comes back to him in a rush. Lydia's voice, when she finds it, betrays very little, "And what, pray tell, is that supposed to be?"

Chris Argent smiles. He really hasn't gotten any better at it since Stiles last saw him try out the expression. " _That_ is the skull of an incubus demon who will plague these hills no more."

"An incubus skull?" Lydia sounds so skeptical that there's a moment where even Stiles finds himself second-guessing whether the thing is really real. "Fished from the bottom of a lake, perhaps?"

 _Ouch_.At least no-one's watching to see Stiles wince. It's thanks to him that Lydia knows what really happened on that hunting trip – and though it's _possible_ Lydia might have made that jab about the lake anyway, he kind of wishes she'd be a little more subtle.

"My lady amuses us." Chris' smile widens – oh _god_ , can't they just insult one another openly like normal people? "Don't mistake my meaning. This specimen suffered a far more recent demise at your humble hunters' hands."

A flicker of a wince rushes across Allison's features, and Stiles realises in a rush of inspiration that this might be the first actual lie Chris has told tonight.

"If I do not mistake your meaning further, Mr Argent," says Lydia, "then may I take it this trophy represents the last remains of the very beast that rid us of those two so sorely missed members of my own household, not four weeks since?"

"You may indeed-" Chris may have meant to say more, but Lydia is not inclined to be patient.

"And is it your expectation, then, that with the death of this _third_ beast, we may at last suppose ourselves rid of this plague of devils?"

"Miss Martin, I am sure that for even so many as _three_ such creatures to invade such humble lands as these is an event without precedent," says Chris, pronouncing each word as if delivering an ultimatum.

Allison stares straight ahead, shoulders rigid, refusing to make eye contact with anyone.

"Well, I am sure we shall all of us sleep easier in our beds tonight for your good work," says Lydia. "In the meantime, if you are quite done upsetting our appetites, might we have you and your good men seated so that dinner might be served?"

It's only natural that Lydia would wave to Stiles here – waiting with the other servants for her signal – though the look she throws him conveys something more. Stiles shrugs back, attempting to convey as much as he's able that what's on the hunters' tray represents no part of Derek's person, and he's got no reason to be concerned. Well, not about _that_ particular possibility, anyway.

He still needs to talk to Allison tonight, once they've all survived dinner – no matter that he's starting to doubt that poor skull could have any real secrets left to its name.

* * *

Allison's bedroom is on the second floor of the Tower, and boasts only one window. Scott's long since mastered the art of sneaking in through it without hardly the telltale whisper of a single claw against the masonry, but Stiles is a mere human being. The task of scaling two floors of sheer wall – let alone silently and in the dark – is well beyond his mortal capabilities. Fortunately, Allison is no mere human. She's a _hunter_ , and an Argent at that: she comes to them.

She meets him and Scott in the shadow of the wall. Though the road is now more than twenty-four hours behind her, the vague aroma of horse hasn't yet left her (though any passing impulse to comment on it is readily silenced by the look on her face that manages to suggest, even in the dim light of the moon, that a proper bath has been the _least_ of the matters she hasn't had the time to deal with since arriving home). She skips greetings altogether. "The skull _didn't_ come from here. If you look at it up close it doesn't even look the same – it's smaller, the teeth are different – I didn't get to see the body, but I can vouch for the hunters who did. They had no reason to lie to us."

"Just to Lydia?" says Scott.

Allison twitches and looks away, her mouth going tight and thin. "My father didn't even tell _me_ what he was going to do in there. He knew I'd argue. He still thinks I'm too close to Lydia for my own good."

The urge to say something _really uncharitable_ about Allison's family bubbles briefly and unhelpfully up through Stiles' awareness. He pushes it aside and says, "We need to know where it really came from," instead.

"The Chastels are an old hunting clan – allies of my family," Allison explains. "We met them on the road just outside of Corton. They're the ones who found the body."

" _Found_ the body – they didn't kill it either, right?" asks Stiles. Allison shakes her head.

"Stiles thinks he might know who it was," Scott puts in.

Allison looks at him, surprised. "Who – you mean the demon?"

"Derek mentioned a friend of his once – a succubus called Laura." Stiles isn't so comfortable sharing this with Allison as he had been with Scott – Laura is more than Derek had trusted even to _him_ until every other secret that mattered was out, and Allison's a hunter, whatever else she may be. But what little hope they have of ever making sense of this hangs on making the most of every scrap they've got. "She died before the rest of this even started."

"That adds up," says Allison, nodding. "If the dates they gave us hold, this demon was killed a few days before everything started here."

"Can you tell us where they found her?" Stiles asks. "The body, I mean."

"Another clan called the Antoines disappeared back in August," Allison explains. "The Chastels went looking for them. A villager who spoke to them not long before they vanished was able to point the search party in the right direction. The Antoines were following a report of a flying, man-sized shape seen coming and going from somewhere in the woods. The Chastels found their bodies nearby."

"Wait, bodies? As in more than one body?" Stiles asks, stomach sinking. Derek had given him the very clear impression Laura was ambushed alone.

"They found the demon's body lying in a ring of the bodies of every member of the clan," Allison tells him, rather less gently than she might. "They killed each other, Stiles."

"But... Derek said the rogue killed her. The same incubus that attacked Lydia!" Stiles protests. "That's how he picked up its trail to start with!"

"Did he see it happen?"

"Well – not exactly. Look, it's a demon thing, I don't get exactly how it works."

"Stiles," says Allison, her voice firm, "whatever killed those hunters had _claws_ , and the demon's body had _twelve arrows_ sticking out of it when they found it."

" _All_ of them killed each other? Not one survivor?" asks Scott, incredulous.

Allison seems unmoved. "It's not unheard of."

Stiles turns to Scott, who looks back helplessly. "Maybe it wasn't Laura after all?"

"If the dates they gave us were right, it all happened two or three days before Lydia was attacked," says Allison. "That's the biggest mystery about this – it's too close to be a coincidence."

"No, you're right," Stiles agrees, if grudgingly, "that's right about when Derek would've started tracking the rogue too."

"Could the rogue have been there as well as the hunters?" suggests Scott. "What if _it_ was hunting Laura, and _it_ was the demon the locals saw? It wasn't as careful about being seen by humans as Derek and the rest are. Maybe it led them to her."

"That's still a lot of a coincidences to account for," says Allison, "but otherwise it might not be a bad theory."

It's really not a bad theory, but Stiles has already been through a few too many not-bad theories today to have much hope left that the answer is going to stay that simple. "I don't like this. There's something else going on here."

"I agree," says Allison, folding her arms. "That's why you need to talk to Derek and find out what that something is before my father does."

"I would, but he's not due back until tomorrow night." This is an admission that comes with no small personal frustration. Isaac's best guess as to how far away Derek had been when he sent his message had started with 'probably somewhere about...' His estimate of how long it would take Derek to fly that far in a hurry had been even less convincing.

"What are the other hunters making of all this?" Scott asks.

"Well, there's some good news for Lydia," says Allison. "All of this happened so far away that no-one can think of a way she could've been involved directly."

"Your dad still thinks she's guilty of _something_ ," says Stiles. "Why else would he lie to us like that?"

"My father knows _less_ about what's really going on here than we do. He doesn't have a better theory," says Allison, in a tone that reminds Stiles that complaining about her father is her prerogative and everyone else's privilege, and leaves him mildly relieved when she changes the subject and saves him from having to do so himself. "And speaking of things _we_ know and _he_ doesn't, there's something else you need to know: I found a few pages on volkodlaki in the Chastels' library. It's not much, but it might help us narrow down where they came from."

"Did it say how to kill them? And make them stay dead?" asks Scott. Stiles gestures enthusiastically for her to tell them absolutely everything she so much as half-remembers, preferably right now.

"Yes and no," Allison replies. "According to their source, a volkodlak comes to be when a demon without a body of its own possesses the body of a dead werewolf. That's why killing it doesn't always work – destroy one body, and a strong enough demon will move on to possess a new one. It can keep happening as long as there are bodies available."

"That would explain why we've only ever seen one at a time," says Stiles, already putting the pieces together.

"Why always werewolves?" asks Scott. "Could it possess a dead human too?"

"In theory, yes, but they prefer werewolves because their bodies are stronger and heal more easily. A human body has to be fresh, or it needs some catalysing event to let the demon in – most demons aren't strong enough to possess a human while they're still alive. A dead werewolf gives them more to work with."

Scott looks slightly confused. "That's not how it works for incubi, is it?"

"No, incubi need a living body to hang around in this plane just as much as the rest of us do. They don't get the chance to go hunt for a new one after they die," Stiles explains. "This has to be some other kind of demon. Did the book say which?"

"The text I found made it sound like there are a few different species that could possess a werewolf's body, usually connected to a failed summoning – something that brings a demon to this plane but fails to install it in the vessel intended," Allison explains. "In theory, that leaves it vulnerable to a banishing ritual..."

"...but not without capturing the demon alive, or at _least_ knowing what kind of summoning brought it here to begin with," Stiles finishes for her, almost without having think about it. After all his work with Lydia, the ritual mechanics of messing with demon souls are still fresh in his mind. "Hey, Lydia might be able to-"

" _Lydia_?" The look of disbelief on Allison's face stops him in his tracks. "Stiles, it doesn't matter what Lydia _might_ be able to do! What she needs to do is _not_ be involved in any of this. Kate and my father will use _anything_ they can find against her." Only with that much laid down does she stop for breath, before adding, "And _I_ need not to hear anything my oath as a hunter would require me to pass on to my father," at somewhat lower volume.

"Message received," says Stiles, already dealing with the glum possibility that this whole conversation has effectively got them nowhere, if only by the most circuitous possible route. One other detail comes back to him. "Allison, there's one more thing we have to ask. Do you have any idea who could've taken the skull from the other incubus? We went looking for it today and it was gone."

"It wasn't us," says Allison. "But if it's missing, that's one more coincidence I don't know how to account for, and I don't like it."

"I don't like _any_ of this," says Stiles. It doesn't help him feel better.

"So where does this leave us?" asks Scott.

Stiles exchanges glances with Allison, but finds no help there. "Derek's supposed to be back tomorrow. I'm going to have to ask him how sure he is that Laura really died the way he thought she did. Then I'm going to have to tell him we've lost the head of the demon who probably killed her, and that the hunters probably found her body. Looking forward to it already."

Scott grimaces in commiseration. "You want back-up?"

Stiles sighs. "No, I don't think him finding out I've shared what he told me about Laura with everyone I know is going to help. Thanks though."

"It's the only avenue we've got," says Allison, with what might be real sympathy. "We can reconvene tomorrow night if we need to."

 _If this hasn't all gone to hell by then_ , Stiles thinks morosely on his way back inside, surprising himself with his own pessimism. Too much of the day has been a progression of one unpleasant surprise after another for him to have much hope left that this mess is going to have an explanation he likes.

Allison's right, unfortunately. Theorising about this on their own time has got them exactly nowhere. Which means there's nothing much else to do until Derek shows up.

* * *

The new day dawns to the news of the death of another man – a Friar who'd been visiting a hamlet only a few hours south of the Tower. The messenger reports that the victim's body was found lying prone in the dirt out in the open, his face twisted in agony, his skin white and shrunken.

Stiles isn't in the main hall early enough to see the hunters' reaction to the news, or Lydia's, or how either party handles the self-imposed obligation to pretend that the event is in some way _unexpected_ , in the light of how the demon responsible is supposedly dead. Whatever thinly veiled accusations might have gone flying in either direction, he misses out on altogether.

Mostly, he's not feeling any great loss on that front.

* * *

The worst thing about being set to scrub the kitchen floors – the worst thing, that is, _apart_ from the smell, the rat droppings, the inevitable discovery of the remains of some species of mouldering vegetable in at least one overlooked corner, and the equally inevitable second-skin of soot and grease that lingers on long after your best efforts to scrub yourself free of it – the worst part left even _after_ the long list of other miserable things, was the hours of mind-numbing tedium required to do the job properly. Almost anything is better than having to think about what you were doing, so the mind wanders out of self-defence. By midday, Stiles has mould under his fingernails, two wet patches expanding to colonise his breeches from his knees outwards, a taste like rotting turnip settled stubbornly into the back of his throat, and has spent more than two hours stuck in a room with only Isaac for company – two hours he's spent _not asking_ the questions he's been turning over in his head all morning. For all that Stiles has officially forsworn wasting any more effort trying to find an answer to this intractable riddle (one the universe seem determined to deliver to him out of order, and only one line at a time), actually getting his mind off the subject has proven easier said than done.

The sound of the bristles of Isaac's broom scraping over the floor is the only sound in the kitchen whenever Stiles stops. He sits back on his heels, breathes out, and is about to scrub a hand down his face before he thinks better of it. To _hell_ with this. "Hey Isaac... about why Derek would've wanted the rogue incubus skull..."

"If you're asking if I've heard from him since, the answer's still no," says Isaac.

"Yeah, I figured. But about what you were telling me before, about how you can see how a demon died if you look into its eyes," Stiles peers back over his shoulder, locating Isaac on the far side of the table, "is there any way you could see back further? Not just the moment it happened, but say – say when it died, its life flashed before its eyes... could you see that too?"

"Maybe," says Isaac, leaning on his broom. "I've never done it myself, so I don't really know what it's like. Mind you," he adds, with a bitter twist to his mouth, "up until last night I'd never even seen one of us dead before."

Had Stiles been paying less attention, he would likely have written that last part off as a minor aside or random non-sequitur, but it's not for nothing that Stiles has been second-guessing the idea of bringing the subject up all morning – and that thing Isaac just said is no small part of the reason why. "We don't know for sure if that was Laura yet," he offers, awkwardly trying to head that whole line of thinking off at the pass. "We don't know how _any_ of this is supposed to add up."

"And I know it wasn't them that killed her." The broom connects with the floor again with some force. "But if they want us to think they did that badly, who're we to argue?"

There is so much in that statement that needs to be unpacked (and then preferably tossed onto the nearest midden before it festers into something diseased). But Stiles is woefully under-qualified for this sort of problem, and if he lets himself get side-tracked now he may never come back to what he really needs to ask. "But Derek thought it was the rogue that killed her, right?"

"Is this about the missing skull?" asks Isaac, throwing him a quizzical look.

"No, it's about where Laura was and what she was supposed to be doing when whatever happened to her... happened." It hadn't mattered back when Stiles had thought he knew what killed her. Now, he's starting to recognise how little he knows at all. "Derek said he was separated from her when it happened. So where did she go?"

Isaac looks suddenly cagey, but he shrugs as lightly as he can manage. "Nowhere she hadn't been before."

"Meaning?"

"She went to check on the Sleeper," says Erica from in the doorway, startling Stiles more than he feels is called for. Boyd is behind her.

"Excuse us for butting in, but the conversation down here was starting to sound important," says Boyd.

"No, by all means, come on in." One of these days, the fact Stiles can apparently no longer have a private conversation anywhere in the Tower is going to become a serious point of contention around these parts, but today is not that day. " _Anyone_ who can tell me what the hell is going on here is going to be my new best friend. What's this 'sleeper'?"

"What Laura went away to check on," replies Erica, unhelpfully.

"Yeah, I got that, I was hoping you might have a littlemore information." Stiles' remaining patience with this subject is wearing rather thin.

"That's kind of the point, though," says Boyd. "If you want to know more about the Sleeper, you'd have to ask Derek. Laura always did used to spend more time on the move away from the wagon than any of the rest of us. Sometimes it was scouting ahead, sometimes visiting old friends, sometimes checking up on the Sleeper. Ask who the Sleeper is, and they'd tell you 'who Laura's gone to check up on'. She and Derek didn't like to talk about it more than that."

"He was definitely some kind of demon," Isaac supplies.

"I had the idea it was an old friend of theirs under some kind of curse," says Erica.

"I always thought it sounded more like a punishment than a curse," says Isaac. "Someone who broke the rules and didn't get away with it. The way Derek talked about it he was some sort of bogeyman. The kind of thing your parents use to explain why you can't go out alone at night."

"Broke what rules?" Stiles asks. Didn't Lydia mention demons who only manifested once every hundred years? She hadn't called them 'sleepers', but it doesn't sound like that much of a stretch.

"That would be another question for Derek," says Erica, with an apologetic shrug.

"Did they mention _where_ he was sleeping?"

"Somewhere out east, I think," says Boyd. "Laura would be gone for days whenever she went to check up on him if we weren't already out that way."

"How often did she go?"

"Every couple of months," says Boyd. "Not to the dot, but close enough."

"So Laura regularly flew the same way and landed at the same place," says Stiles, pushing the whole 'sleeper' issue to the side for the moment. "Okay, I think I see where this is going."

"You think someone saw her and figured out when she'd be back?" asks Isaac.

"There's no 'think'; I _know_ someone saw her. The hunters only found her because someone tipped them off to where she'd been seen." Stiles rubs the side of his head. "Maybe someone tipped off the rogue too. All he'd have to do is shift into human shape and ask the right questions. Or even just follow the hunters." It's not much of a coincidence that both he and the hunters would ambush Laura in the same place if it's the one place anyone knew to find her.

The other three appear to digest this.

"There is one way to find out for sure," says Isaac.

Yeah, and that would be one of the other reasons why Stiles wasn't going to bring this up. "We're gonna have to get hold of her skull, aren't we?" he says, already resigning himself to this fact. "Fine. I'll go talk to Allison."

* * *

He catches Allison on her way out. Most of the hunters are about to head off on regular patrol, checking for recent werewolf tracks or harassing local peasants or whatever else it is they do to look busy. Allison won't sneak the skull out for him, and she won't give him the key to the hunters' quarters either. However, she _is_ willing to lend him a key to one of their cabinets (much as that request confuses her), describe where the skull is being kept, and assure him that almost no-one should be in their quarters between now and supper.

Stiles brings the key to Boyd, then they both shut themselves in the armoury. The rush of cold after Boyd turns the key in the lock is as sharp as Stiles remembers – nevermind that _this_ door leads only to a slightly more distant room in the same building, and nevermind that Boyd opens it only a crack. He peers through, then turns back to Stiles and nods.

Stiles leans against the door frame and peers cautiously through the crack. After several seconds of effort trying make sense of what he can see on the other side without success, it dawns on him that his whole frame of reference is wrong, because _down_ has snuck around to his _right_ while he wasn't looking. Only with a feat of great concentration does he succeed in edging himself away again.

"Problem?" asks Boyd.

"Everything's _sideways_!"

Boyd shrugs, as if a minor misalignment of the dimensions is only to be expected. "That's what happens when the doors don't open the same way. Your hunters' 'cabinet' seems to be more of a _trunk_. Can only work with what we've got."

"Of _course_ ," Stiles grumbles. He steels himself and nudges the door a little further before peeking through again.

Understood through the correct orientation, the hunters' quarters resolves into its usual state of organised clutter. The good news is there's a half-empty bookshelf standing right across the room from him, with a suspiciously skull-shaped object under a cloth sitting on its second shelf, right about where Allison had led him to expect it ought to be. The bad news is that there's a man sitting between Stiles and it, apparently engrossed in a partially disassembled crossbow lying in front of him on the table.

Stiles only vaguely recognises him, his name might have been Ben-something, maybe? While the Argents have been a fixture at the Tower since he was young, most of their lackeys come and go on some sort of journeyman rotation that keeps news and rumour on the move through the hunter community. Few are properly introduced on arrival; even keeping track of how many there are based at the Tower at any one time drives the cook to distraction. The hunters are a law unto themselves, their community closed to outsiders, and their underlings clearly aren't encouraged to mingle with the locals. They stick to their own tables at dinner, and they don't talk to the servants more than they have to.

The long and short of it is that whether probably-Ben might be, say, deaf in one ear and prone to tunnel vision when he's working – or whether he's more likely to have the reflexes of a cat and a hair-trigger reaction to moving air behind his back, Stiles has no idea whatsoever. Ben-the-hunter is an unknown quantity, therefore the only safe option is to assume the absolute worst. So all Stiles needs to do is climb out of the box, tiptoe across the floor, grab the skull, tiptoe back, climb back into the box and pull the door shut behind him without making a single telltale whisper of a sound, and especially without accidentally tripping over anything or bumping into anything that might thump loudly and give him away.

Stiles carefully drops back into and/or turns away from the open chest/door again, easing it closed behind him. "There's still a hunter in there!" he whispers.

"Did he see you?" asks Boyd.

"Not yet, but that doesn't mean he's not going to if he hears someone climbing out of a chest behind him!"

"Fine," says Boyd. "I'll go knock on the door and get his attention. You get the skull."

Stiles can't help but feel there's a flaw in this plan somewhere. "You're going out there now? But... how?"

Boyd raises his eyebrows at Stiles, pushes the door open and steps out into... the hallway outside the armoury, letting the door swing closed behind him. The sound of his footsteps in the corridor gradually recede away.

Okay then. Who's Stiles to argue? Other than the guy left to work the fairy-magic-door-trick for himself all _on his own_.

At least half a minute goes by before Stiles works up the guts to try the door again himself. He honestly has no idea what he expects to see on the other side.

He finds himself looking at a side-on view of the hunters' quarters, the lone hunter no longer in evidence, and the sound of voices coming from somewhere below. Or possibly to his left. One of those things.

If Stiles stops to think about this properly, Boyd will have run out of things to say at the door and left again before he's moved a muscle. He takes a deep breath, pushes the door open and focuses hard on the world on the other side. Then he very carefully climbs out of the chest and puts both feet on the floor.

He can see the hunter at the door now, in a small ante-chamber that separates the hunters' main meeting space from the outer door. Boyd is faintly visible through the far door, where he's emitting so much glamour he practically _glows_. Some time later, Stiles and Boyd are clearly going to have to have another Serious Talk about indulging in showy displays of magic in front of the very people trained to spot it. For now, Stiles will stick to being thankful that Boyd seems to have the hunter thoroughly distracted.

With the exaggerated care that comes from years of sharing living space with a guy with werewolf-hearing, Stiles tiptoes his way across the room.

The object under the shroud on the shelf does indeed turn out to be to be the skull he came here for. He's just about to take both skull and cover and go when it occurs to him that the smart thing to do would be to find something else of roughly the same shape to stick under the shroud in its place. He scans the room for some sort of suitable replacement. A pair of manacles hanging from the wall by a length of thick chain look promising for only as long as it takes for Stiles to realise there's no way he'd be able to move them silently. He settles instead for a miniature wood carving of a snarling wolf's head, though he has to place it with the snout towards the wall to make it work. The result isn't going to fool anyone on the look out for a fake, but should hopefully pass muster just long enough to stop anyone looking more closely. He wraps the skull in a rag from a basket behind the book-case instead; touching it with his bare skin gives him the willies.

Throwing one last nervous glance toward the door, Stiles tiptoes back to the chest and climbs in, pulling the lid carefully down behind him so that it shuts with barely a click.

He makes it back to the armoury with his heart still pounding in his ears. Boyd's not back from downstairs yet, obviously. Come to think of it, he's probably not getting out of this room at all until Boyd comes back to let him out. Which makes this a pretty sound window of opportunity for one more thing that needs doing before he loses his nerve.

Stiles sits down on the floor, carefully cradling the demon skull in both hands. No, not just 'the skull' – _Laura_. It even looks a little like a Laura now he's got a moment to examine it properly, or at the least Stiles is doing a pretty good job of making himself _believe_ it looks like a Laura, and belief is the earth upon which all practical magic is founded.

"So. Laura. Hi," Stiles says aloud, feeling only slightly ridiculous. "I'm Stiles, nice to meet you. I'm Derek's... well, that part's complicated, but if you were still alive, I'm sure he'd have introduced us properly by now, so there's that. And I don't even have the words to express how much I wish we could be meeting under better circumstances, but this is what we've got, and apparently this only works if I know you so... well, here goes..." Stiles tips the head towards himself and looks deep into the empty sockets of its eyes.

Several moments and one small eternity have elapsed before Stiles comes back to himself again, with a rush of vertigo not even Boyd's door trick could compare to. He's not quite done congratulating himself on having the forethought to _sit down_ before he tried this when someone throws open the door.

Stiles is about halfway through hurriedly shoving the skull behind his back before he realises it's Isaac. "Didn't you hear me calling you? Derek's here!"

" _Here-_ here?" Stiles splutters.

"No, he wouldn't fly to the Tower in daylight," replies Isaac, sensibly. "He's waiting for us out in the woods, I can show you where. Did you get it?"

Stiles hefts the skull feebly and pushes himself to his feet. The room spins briefly around some unidentifiable fulcrum, but this is no time for nausea. "Yeah. Yeah, let's go."

On the ground floor, Erica is waiting for them at the door, arms folded. "I'm coming too."

"You don't have to," says Isaac.

"No, I really do," replies Erica, and that seems to be the end of it. Stiles follows Isaac out of the Tower and down the hill, Erica bringing up the rear. He should really pass the skull to one of them – he'll move more easily with his hands free, and he's the one slowing them down the most, but the thought only makes him clutch it tighter. That lump of bone has come to represent the only hold on the situation he still feels as though he's got.

They find Derek waiting for them in a clearing about ten minutes' walk away, his expression cold and grim. The lines of his face seem to invite more shadow than the hour supplies; his posture is all edges, and the look in his eyes stops Stiles cold ten feet away. For a long moment Stiles almost doesn't recognise him.

Mentally, Stiles kicks himself – what the hell did he come here expecting, anyway? It's no-one's fault but his own if he's not the centre of Derek's world anymore. This just happens to be the first time since the night they met that Derek isn't here for him.

In a voice possessed of none of the warmth Stiles is used to, Derek asks, "Did you bring the skull?"

"Not exactly." Stiles' throat feels dry. Even with the weight of Derek's gaze boring heavily into the cloth-wrapped bundle he's so conspicuously brought to this meeting, the skull itself feels deceptively light in his hands. "We looked for the rogue incubus' skull, but it was already gone, no way of knowing where or how. The good news is the hunters brought home a replacement when they got back."

A sharp intake of breath. " _Whose_?"

An hour ago Stiles had still nursed some lingering measure of doubt on this account. It's gone now. "Who do you _think_?"

Derek holds out a hand. "Give it to me."

The command in Derek's voice rings so loud that the bundle in Stiles' hands seems almost to jerk forward of its own will – but playing along so readily isn't an option anymore. "I need you to tell me something first. Who's the Sleeper, Derek?"

In his peripheral vision, Stiles is barely aware of Erica and Isaac staring at him in confusion. The surprise that flashes across Derek's own face is brief; it melts into something sharp and angry. " _Stiles_."

There's no missing the warning in Derek's tone, but Stiles ignores it. "That's where Laura was when she died. Who's the Sleeper?"

Derek exhales, short and angry. "You ever wonder what happens to one of us if we break a geas, Stiles?"

If this seems like a non-sequitur at first, a second thought is all it takes to send Stiles' imagination running wild. If Derek's under a geas that prevents him sharing this information... that might actually explain a lot. _Goddamnit_ , that would be the last thing they need. "Something different to what happens to humans?"

With a twitch of one side of his mouth, Derek shares what may be the most humourless smile of their association. "We don't get off that lightly. The geas binds you, but it _derives_ from us. That makes all the difference." He takes a breath, fixes Stiles with his gaze. "For us, the price is pain. Seven years of agony without respite. Some hold out longer than others, but no-one survives."

An involuntary shiver runs its way down Stiles' spine. Derek keeps talking.

"Laura had a mentor of her own, once. What he did, he did to protect us. When we found him, he was clinging to this world by a thread. We couldn't help him, but we found someone who was willing to try – a witch with some skill in the demonic arts. She bound his soul beyond the reaches of his body, but the pain found him even there, so she sealed him in a dreamless sleep to wait out his sentence in oblivion. We laid him to rest in the tomb of a forgotten king. He should have been safe there, but Laura would go several times a year to make sure."

Stiles can feel his own heartbeat hammering in his ears. His eyes must be wide as saucers. Derek's story is a mess of jagged fragments, sketching between them only the edges of a horror beyond contemplation.

Derek looks away. "Does that answer your question?"

It takes him a moment to remember how to speak. "No, I... yeah, that is..." Mutely, Stiles holds out the skull, mind racing. Derek's footsteps crunch heavily through the low carpet of bracken as he comes to take it. He unwraps it slowly, letting the cloth fall away from the blackened bone beneath. He turns away then, but Stiles would swear he sees Derek's hands actually shaking for a moment before the broad plane of his back conceals them from view.

Stiles doesn't see him look into it. But then, he knows this part – he doesn't need to.

* * *

_The first arrow tears through the flesh of her right lung in a trail of fire. The sight of the shaft protruding from her chest confuses her for one wasted moment of shock; it doesn't make sense that it should be cold and dark, not while its head sears her body from the inside out. This is not at all what one should be thinking after being shot, but now her breath is gone and she can't make sense of why. It's too late now to contemplate what a fool she's been, to suppose she could visit so often without any mortal eye taking note of her passage. Her enemy has taken her tired and unaware, but one arrow is not enough to fell her. She is old and strong, and in a moment her rage will find her, and she'll show them how very right they were to fear her kind._

_The image of the shaft protruding from her chest is all she's granted time to comprehend before another joins it – and another, and another still._

_They don't all find their target. One goes whistling past her elbow, another whizzes through the curtain of her hair, but the eighth finds her throat, and the fifth her heart._

_If she could draw breath now, she'd scream. The pain is blinding._

_She falls, writhing as her talons rake the dirt for purchase, and it dawns on her with a slow and sickly light that she is dying. It is not the pain alone that will kill her, though every cell of her body swells with it as if readying to burst with agony – she cannot, **will** not give in to that, here of all places. The shame of such weakness on his very doorstep would follow her far beyond the grave. But her body is failing, its life is leaking out around her, and with it, her one true anchor to this world is coming loose. She can already feel her mortal form returning to that same dead matter as the earth on which it lies, her hold on the mortal plane dissolving like sand in the tide. There are human voices in the woods, flickering in and out of her focus and understanding. In desperation she lashes her will to the very pain itself, but even that last gasp is failing, melting with her own black blood into the grass beneath._

_Even as she fails, she feels the rage she sought reaching her at last – but it comes from without, boiling up from beneath the earth in wave upon wave, tearing the ancient mound asunder as though hell itself were opening to receive her. Rage like none she's ever known in life will be her legacy, her funeral-dirge – will rise, phoenix-like, to avenge her passing._

_But its heat can scarcely reach her, its voice she barely knows, her fading spirit is too far gone to either rejoice or weep in knowing that the score she leaves behind will not be allowed to go unsettled._

* * *

From Derek comes a shallow gasp, the skull tumbling from his hands to vanish into the bracken at his feet. His knees go next, though a little more gently.

It's hard to say who calls his name and dashes for him first; only that Stiles comes up short one useless step from Derek's back, Isaac on his right, by Derek's left shoulder, and Erica opposite, hovering uselessly in triangular arrangement, with none of them sure enough to decide whether the touch of a hand will make this better or worse. Even in despair, Derek radiates something that warns comfort won't be welcomed.

From as long ago as their second meeting, Stiles has clung to the idea that there are _two_ kinds of incubi in the world – the kind that had emerged, life-sized, from the horror stories in his books to assault Lydia in her own bed, and Derek's kind – who don't kill, and who masquerade as human as well as Scott at his best. If that was naïve of him, it's the only way he's found to make sense of the idea that both Derek and the red-eyed monster that grinned at him from across Lydia's room that night could ever have belonged to the same species at all.

Now the red-eyed monster has been one of Derek's own all along. Stiles doesn't know what he's supposed to do with that. It beggars understanding.

"I didn't know," Derek whispers, and Stiles reaches for him without thinking.

He's hardly touched him before Derek flinches away under his hand. He turns to look at Stiles, a fury in his eyes that burns with something sharp and treacherous. "You saw."

'Saw' doesn't begin to do the experience justice. A tiny part of Laura is lodged in Stiles' head, vivid now as it was when he first got his breath back – like the aftermath of a nightmare the length and shape of someone else's lifetime, all squeezed into the space of a night.

"I had to know, Derek." Should he have tried to make that sound more apologetic? It's only the truth. It doesn't matter how much he trusts Derek (or wishes he could) – Stiles had known long before he looked into Laura's empty eye-sockets that the truth would be more than he could risk handing away blind. Much as he might wish he could've been wrong just this once, knowing the truth hasn't changed that.

"You had no right," Derek growls.

"No," says Stiles. "But I would've done it anyway."

"Would you?" Derek's teeth close over the accusation as if to rend the very thought. "Even now, knowing what you'd see? Is there _satisfaction_ in having seen her die? In knowing who I really killed to save you?"

For a second, Stiles is dumbfounded. It passes, because there's an answer to that, and none of them have the right to forget it. "Derek, he was going to _kill Lydia_. Why? She wasn't even part of this!"

Derek's lips curl into a snarl. "Don't imagine for one _second_ that I tore out his throat for her sake. Or yours."

Stiles feels numb; there's no script for dealing with something like this, not that doesn't come from Greek tragedy. There's a part of him that knows Derek's lashing out at him only because the alternative is to take it out on himself – knows that he'd _known_ that much, on some level, or he'd never have offered himself up as a target to begin with. There's a part of him just barely beginning to recognise the first glimpse of what Derek must be going through – not just that family could be so corrupted, but that Derek himself had... but Stiles can't dwell on that, because it's beyond all comprehension. He can't look into _Derek's_ eyes, or run his fingers over his skin and understand as easily. But there's another part of him that hates Derek in that moment, or wants to – hates him for being wrong about the rogue, hates him for ever letting either of them believe any part of this could be so simple – for bringing any of this into Stiles' life to begin with.

A strange, stuffy feeling of detachment is apparently the only way to add all that up and get anything he recognises at all. He's still casting uselessly for what he's supposed to do with any of this when someone else says, "Derek?" – a scared, fragile voice that Stiles almost doesn't recognise.

He and Derek startle and turn to stare, both having all but forgotten they're not alone.

Isaac actually flinches slightly under their attention, eyes wide. He's shaking. "Derek," he stammers, "what's this about? What did you see?"

Derek's rage stutters out, guilty as Stiles of letting himself get carried away. Behind Derek, Erica has fished the fallen skull out of the bracken; Stiles sees her clutch it to her chest, though she's holding it with the eyes turned down. She hasn't looked into it yet.

Derek looks helplessly between the two people who are to him what he was to Laura, what Laura was to her own mentor, then looks away, as though unable to look either of them in the eye.

"I was wrong." Derek's answer begins clear and slow, his voice pitched to be heard. "It wasn't the rogue who killed her. There _was_ no rogue – only him. It was humans who tracked her, who ambushed her and left her to die. When she fell, it was her death that woke him. It was him all along."

"Him?" echoes Isaac. "Who's..." The exact moment he begins to put it together happens there, in the open, for everyone to see. In the corner of his vision, Stiles sees Erica go white, her hold on the skull between her fingers tightened into a death-grip. Isaac sounds like he's pleading when he speaks again, "Derek? How...?"

"I didn't recognise him. Not even when..." Derek halts, the statement left to hang in horrifying potential. There's something of a confession about his voice when he starts again. "We were both of us too blinded by rage to know each other. But after waking like that, he hardly knew himself. So many years of waiting, the pain never truly left him, even in sleep. All for what?"

Derek's voice cracks on the last word, his head bowed, his shoulders heaving silently, and in his chest, Stiles' feels his own heart close up; not break, but freeze. If he were able to feel more than the roughest edges of what Derek's going through right now, it might never start again.

It comes to Stiles that his true mistake wasn't to look into the empty sockets Laura's eyes, it was in not smashing the skull to pieces on the floor the moment he came back to himself, before it could ever share its grisly secret again.

As if sparing Derek this was ever an option.

What's left is a fever-dream of scraps and madness, where Stiles understands just enough to be denied the least remnant of comforting doubt. In Laura's memories, the all-consuming rage of her mentor was fresh enough to taste, like hot ash in the back of his throat. Rage like that could easily carry someone halfway across the country before it burned out. The bloodied carcases of every hunter to take part in his scion's murder would barely sate the edge of it. And yet, that same rage wasn't wholly alien because Stiles had seen it once before – in the eyes of the incubus that had grinned at them with glee as it discovered the only inhabitants of the Tower helpless to stand against it. He still remembers the horrible moment of insight that had told him it was _glad_ to have been caught; that it had left only to grant them all a day in which to know despair before it returned to kill them all.

The Sleeper might be a being worthy of sympathy, of pity, but the monster that appeared at Lydia's window that night... Jesus, how could that be anyone Derek had ever called a friend?

How could that be _Derek_?

Maybe this isn't the moment to say as much, but Stiles has never been known for his patience. The discipline to hold himself quiet while others grieve or pray to the same god who let this happen, to be still with his nails in his palms while the words build and scratch at the lining of his throat – none of it has ever come to him easily. If he doesn't speak now, Stiles may burst with it.

"Derek," he hears himself say, "if you hadn't stopped him, he would have killed us all."

At first, the only sign Stiles has been heard is that Derek's back goes tense. Slowly, he raises his head and turns to face Stiles, eyes burning.

Stiles feels himself swallow, has to work to keep himself from taking a step back as Derek advances on him (has to work even harder not to protest that his meagre outburst was the _least_ the situation deserved). "He didn't care who we were! He wanted us to suffer! He wouldn't have stopped with us either," Stiles begins to feel like he's pleading, "You said yourself, he was letting himself be seen, drawing attention to the rest of you that would get you all killed – if that was all he'd done, _that would have been enough!_ "

Only when his chest is inches away from Stiles' own does Derek stop moving. He seems confusingly taller than Stiles remembers.

"No, Stiles," says Derek, his voice a low growl, "he wouldn't have stopped. He would have found your hunters and begun to pick them off, one by one. They would have ridden home with the devil on their heels and found their own tower empty but for the bodies he left for them to find. Do you think they could have stopped him? That a hundred arrows could compare with what he'd suffered? His very soul hasn't been his own since the day we took him to the witch – for _help_. And once he was done, he would have moved on and done it again, and again, until they brought him down, or the land lay ravaged by his fury."

Derek's eyes are glowing a blinding, fiery red – like nothing Stiles has seen from him since he can't remember when. "Could you blame him? Can you tell me there would have been less justice in that than what was done to him? He would have torn out the hearts of every hunter in the land," says Derek, anger rising again in his voice. "And he would expect nothing less of me do to his legacy the justice – the _penance_ it deserves."

The force of air as Derek spreads his wings and launches himself into the sky is quite literally so strong that it knocks Stiles off his feet.

With the dirt at his back, Stiles can only barely make out the shape Derek makes against the sky, receding rapidly into the distance. By the time he makes it back up, head spinning, arms and legs moving entirely on automatic, Derek's vanished out of sight altogether, the only sign Stiles is looking in the right direction at all is that Isaac and Erica are still staring dumbly off the same way.

"Okay," Stiles hears himself say, "someone needs to go after him. Someone with _wings_ , that is."

Erica and Isaac exchange glances, then look away.

"What?" says Stiles.

"He doesn't want me to," says Isaac.

Stiles swallows around an aching throat and wonders how many more gut-punches this day could still have left to deliver. He can't process this. He's probably panicking. That would make sense, right?

Except that he's not panicking. He's tense, upset, _worried_ – but he doesn't seem to be panicking. That's... okay, why not?

As best he can tell, it seems to be because no matter what sort of unimaginable things Derek had so clearly implied he might be running away to do, no part of Stiles believes for a moment he'd really meant any of them.

Huh. Well, that's something. Maybe that's denial speaking – maybe what Stiles needs is an hour or three for the implications to really settle in. He doesn't think so though. And if being pretty sure Derek isn't _actually_ running off to commit mass murder isn't much of a reassuring note to end the day on, it's the first thought he's had that's made him feel like he's got ground under his feet in a while; a moment of clarity he'd badly needed.

He's still feeling his way through that last part when the howl comes out of the woods.

It's not the choked-off scream of the creature that had dived for Isaac's throat this time, or the tortured wail of the dead thing which Scott had beheaded a month ago. There's distinctly more roar and less death-rattle than Stiles recalls from either of its past attempts – practice has apparently done the volkodlak some good on that front – but there's no way to mistake a sound like that as having come from anything counted among the living.

In the back of Stiles' head, that tiny voice that had been muttering all along about how meeting Derek off in the woods was maybe _not such a great idea_ becomes a shriek as the volkodlak emerges from the trees on the far side of the clearing.

Its latest body is – or was – male, a boy probably no older than Stiles himself. Given how easily it could've snuck to within leaping distance of any of them while they all stared stupidly at the sky, it's really quite sporting of it to have bothered to announce itself at all. But the volkodlak's new fondness for showmanship doesn't end there – as soon as it has their attention, it does something Stiles has never seen it do before: it _grins_ at them. On its stolen face, the expression is vicious, built of jagged fangs sprouting from shrivelled gums.

Still grinning, the demon looks at Erica, then casually turns its attention to Isaac. In the back of Stiles' head, the answer to that last lingering mystery clicks into place in a useless rush of insight, which unfortunately has the side effect of leaving him too dumbfounded by this revelation to do more than stare back when the volkodlak's white-eyed gaze finally settles on him. It occurs to Stiles to wonder about the risks of looking into the eyes of a dead demon wearing a dead werewolf's face, known or otherwise. It occurs to him that Scott isn't coming, that Derek isn't listening, and that he hasn't a pinch of mountain ash on hand for protection. It also comes to him that the moment he perhaps might have used to figure out how to get out of this alive is very probably the same one he just wasted.

When the volkodlak predictably leaps for the single person present who _isn't_ lucky enough to have wings of his own, Stiles is in no way prepared for it, and Erica and Isaac almost don't react fast enough.

In the chaos of the minute or so that follows, a number of moments flash by that Stiles will undoubtedly remember. The sight of the demon's face snarling at him from barely an inch away before the instant when Isaac tackled it into the ground. His own voice yelling "the neck, go for the neck!" at whoever might be listening while Erica joins the fray. The sight of blood welling from a series of four parallel gashes in the side of his own arm.

In all that excitement, he must have missed the exact moment when the first arrow shaft appears, protruding from the back of the demon's head.

And that's how the hunters arrive in the clearing _just_ in time to see Erica twisting the volkodlak's arm behind it while Isaac slashes at its throat with his claws.

**Notes for the Chapter:**

> For anyone who may have put it together in advance that the undead werewolf villain = actual Peter Hale, please award yourself some goodly number of points.


	14. Chapter 14

The dungeons aren't the only part of the Tower to have fallen into disuse in recent months, but they've done so with a certain style – one heralded from halfway up the stairwell by a distinctive odour of mould and damp. Not even in Harris's most vindictive moods have Scott or Stiles been exiled to this far corner of the grounds to scrub the floors, and it's hard to imagine the meagre attention of two boys with a mop could have made much difference. Stiles discovers only by experiment how much of the ground under his feet remains waterlogged under shallow, muddy puddles. The few windows here are high and narrow, the ceiling set barely above what is ground level outside, and rainwater has begun to carve thin channels into the masonry between the bars, the fading daylight leaking past with little more enthusiasm. Jagged outer coatings of rust have colonised every piece of metal work below knee-height, and enough of that above to guarantee the cell doors creak in appropriately menacing fashion as they slam behind each of the hunters' three new prisoners.

Boyd isn't spared. By the time the hunters have frogmarched Erica and Isaac home, crossbows trained on their every move, emissaries have already ridden ahead to apprehend the new steward. The Argent clan may be many things (few of them complimentary, in Stiles' personal estimation) but naïve or disorganised they are not.

There was no help to be found from Allison. The one time Stiles managed to catch her eye, the look she'd given him had plainly suggested that whatever the appropriate time might have been to come to her for help in harbouring three _more_ supernatural creatures inside the Tower, he'd missed it by a mile.

The possibility she might have some sort of point there isn't doing much for Stiles' mood. It doesn't especially help that he's is having a little trouble remembering just at that moment some of the finer detail of his own reasoning on the subject – whether it had had more to do with him having halfway-assumed Allison might have already picked up the gist on her own, or whether he'd been presuming the whole subject was the kind of thing she'd find it easier _not to know_ , or whether the fact of two _more_ demons under her roof had had simply been too much to admit so soon after the whole Derek fiasco came out. Besides, he can _absolutely_ blame some of it on Scott, for the crime of having once sort of implied in passing that he wasn't sure if telling Allison was the right idea. Stiles was starting to really wish Allison could just once and for all make up her mind what sort of hypothetical situations fall on which side of the need-to-know/need- _not_ -to-know line, and maybe pass it to him in writing for future reference. This whole polite-fiction system leaves a lot to be desired.

Unfortunately, the rest of the hunters aren't greatly more interested in Stiles' so-valuable first-hand-perspective either.

"Doesn't anyone want to talk about the _other_ demon? As in the werewolf-demon that _nearly killed me_?" he protests, when he can get a word in edgeways. "The one _they_ saved me from? Anyone?"

It turns out no-one really wants to talk about the werewolf-demon that nearly killed Stiles, or that either Erica or Isaac ever saved anyone from anything. No-one wants to talk to Stiles at all. He's got a nasty feeling the only reason he's been allowed down here at all is so the hunters can keep half an eye on him while they gloat.

"Right under our noses this whole time," muses Kate, strolling along the line of cells. "Not quite so obvious as the last incubus who stopped by to introduce himself with it all out on display, I suppose – friend of yours, maybe?"

Isaac hunches away from her as she stops in front of his cell, his fingers clutching loosely over the arrow-wound in his belly. It's healing now, but the hunters hadn't let him remove the shaft until they had him locked away, and the same excruciating poison Stiles remembers seeing in action when Allison had shot Derek in the woods has taken its toll on their prisoners.

"It wasn't _you_ – that's one face I wouldn't forget in a hurry, but that does beg the question: is he still out there, or did we really take him down over the lake two months ago?"

Stiles curls his fists until his nails dig into his palms and hopes no-one sees.

"You'd almost think they wanted to be caught, setting up on our doorstep like that," Kate goes on, oblivious, "but you do have to admire their balls, don't you?"

Erica, Isaac and Boyd glare balefully back at her from their separate cells. From the stairwell, the sound of heavy footsteps heralds the arrival of two hunters, between them ushering Lydia into the room, none too gently.

Lydia's eyes flicker rapidly around the room as she takes in her three newest servants' imprisonment, but her voice attests to nothing but impatience and indignity. "What exactly is the meaning of this?"

"Miss Martin," says Chris in a voice so oily it practically _oozes_ , and in a flash of horror, Stiles experiences a terrifyingly vivid premonition of just exactly how this confrontation is going to go, and just exactly how long Chris is going to take to get to the point. He has officially had it up to his eyeballs with secrets and double-talk.

"He thinks they're _demons!_ " he blurts, before he can think better of it. Squeezing his eyes shut so he doesn't have to see the venomous looks Chris and Kate are doubtless already shooting at him, Stiles squares his shoulders and goes for it. "A dead werewolf tried to kill me, and the hunters saw them _saving my life_ and arrested them for being demons – even Boyd, who wasn't even there. They probably think they're _your_ familiars or something, because of how your mother was a witch."

 _There_. _Was that so hard?_ Stiles risks a peak at the greater room, daring Chris to calculate how much time and trouble Stiles just saved everyone, and spots Scott in the doorway, looking mildly flummoxed as he mouths 'they did?' silently across the room. Stiles shrugs helplessly.

"A _dead_ werewolf?" says Lydia.

"A _werewolf_ ," says Chris, "that is dead _now_." 

A series of hysterical giggles jam themselves in Stiles' lower throat, forcing him to cough violently.

"But during that fight," Chris continues, "two of your precious staff revealed themselves to be more – or rather, _less –_ than human."

Lydia's gaze sweeps briefly and dismissively around the room before returning to Chris. "Remind me, Mr Argent: what _is_ the penalty for saving a human from werewolf attack?"

"For a human, the _reward_ would be at his lord's discretion." The downturn of Chris' mouth suggests he finds very little humour in this perspective on the matter. "But for a demon – one who made the error of revealing its true form in the fray? I think we would better ask the penalty for knowingly harbouring demonic agents beneath the roof of a noble family!"

" _Knowingly_?" The thin seam of hurt and fury which has run just beneath the surface of Lydia's countenance since she stepped into the room seems to ignite all at once. "I nearly lost my _life_ to these demons! How many times need I remind you that? Two of my own household _dead_ at the hands of some beast that has so eluded you and your hunters – who each and every one of you have lied to me time and time again, every time you promised the danger was _dealt with_. You would bring my mother's shame upon my head; you dare suggest I would _invite_ such beings into my own domain?!"

Chris remains unmoved. "And I say to you, my lady, if you are indeed so innocent as you say, then I am sure you will have nothing to fear should I propose a thorough search of your personal effects."

"Every corner of this tower has been searched by you and your kind a _dozen_ times over since the day my mother left!"

"But it's not your mother's misdeeds that are in question now. One more search can hardly do any harm, wouldn't you agree?"

Lydia's eyes flick to Allison in desperation, but find no help even there. Allison looks away. Lydia is cornered and she knows it. "Fine. _Fine_. Just get it over with."

"I'll deal with it personally," says Kate.

Stiles mind is racing before she's hardly moved. Everyone here knows the hunters have searched Lydia's room before – likely several times over this last year alone. The Martins' daughter is far too smart to have left anything for them to find. The hunters _have_ to know that. Then again, if they've already fallen to the level of passing a borrowed skull off as a recent kill, how far can they be from planting whatever evidence of Lydia's wrongdoing they can't find?

Lydia is ahead of all of them. "Scott – why don't you assist Miss Argent in her investigation?"

Scott looks taken aback for all of a moment before some part of what Lydia's really asking for seems to sink in. "Of course." Nodding, he moves to follow Kate.

"Please, don't trouble yourself on our account," says Kate, though she sounds more amused than put out by being saddled with the stableboy.

"I'm sure you'll find a use for him. Perhaps you could take the opportunity to interrogate the few loyal servants I have left while you're about it," suggests Lydia, sweetly.

"Actually," says Chris, icily, "I thought we might begin by interrogating the guilty."

"Does that mean we get to talk now?" calls Boyd from behind him. "Because there's a thing or two I've been trying to explain to your men ever since they burst in on my rooms, only I'm not sure the message has gotten through."

"Let me guess." Chris turns to face the cells in a leisurely sort of fashion, "You mean to deny the charges brought against you?"

"Not all of them," says Boyd. "You're right inasmuch as none of the three of us are human. Sorry, Miss Lydia. We haven't been as above board on that front as we might have been."

"But you're going to deny being demons, I suppose," supplies Chris.

"We're not though," says Boyd. "We're _fae_." He takes in the general surprise in the room without blinking.

" _Fae_ ," echoes Chris, apparently too surprised by this defence to have prepared a better comeback.

"Half-breeds if you want to be specific. I can prove it." Boyd raises a hand and presses it, palm-first, against the iron of the bars, grimacing as his flesh begins to sizzle. He holds the resulting burn up for inspection, angled between the bars like some grisly parody of a badge of identification, and Chris is so unsettled by this turn of events that he actually takes several steps closer to see. He shoots a look back at his men, heavy with meaning – whether he wants to know why no-one brought this to his attention sooner, or simply whether everyone else present is seeing the same thing he's seeing, Stiles can only guess. Allison, meanwhile, turns a questioning look his way. Stiles attempts to communicate that she should maybe be less obvious while people are watching. Lydia just raises her eyebrows at everyone.

"That's how we got past your mountain ash line, if that hadn't occurred to you yet," says Boyd, helpfully breaking up what was about to devolve into impromptu pantomime. "Works on all kinds of magical creatures, but not on us."

"Your associates," Chris argues, "grew _claws_."

"That would be what we call glamour," says Boyd, shrugging the accusation away. "Prettying yourself up isn't all it's good for."

"Intimidation. Tooth and claw." This interjection comes from Erica's cell. She's huddled on the floor, hands curled at her chin, but her voice carries a quiet weight. "It's the only language a creature like that understands."

"Explain to me," Chris demands, "what three half-breed fae are doing washing clothes and emptying the bedpans for a minor noble of a family of broken reputation."

"Do you think 'real' fae have better to offer the likes of us?" says Boyd. "Why, Isaac and Erica aren't even proper half-breeds – that was their mother, and she would've likely given her right arm for a life as comfy as yours. For the record, we didn't kill your maid and steward like you've been insinuating. The real culprit was that creature you saw them fighting in the woods today." Boyd gives that revelation a moment to sink in. "Excuse us for imagining hunterswould be able to tell an ordinary werewolf from a volkodlak."

"A volkodlak?" Chris repeats.

"You're referring to the myth that a werewolf resurrects as a vampire after death," Allison supplies, with what more or less passes for innocent curiosity. Stiles has to give her credit: if he hadn't known she's spent the last two months researching the subject exhaustively, he still wouldn't have any idea now.

"Or a demon wearing the body of a dead werewolf, which feeds upon the lives of mortals to sustain itself," clarifies Boyd. "That's no myth."

"You know, for a half-fae of limited means, you seem to know an awful lot about the subject," says Chris, taking a very deliberate step closer to the bars.

"You'd have made time to learn as much as possible about that creature too if it had been hunting _you_ as long as it's been hunting us," says Boyd, undaunted. "Don't ask me why, maybe we smell better than its usual prey. All we know for sure is that it's been tracking us since midwinter, and every time we think we've killed it, it finds a new dead wolf to wear and comes after us again. Why do you think we were so keen on moving into a defensible Tower, surrounded by mountain ash and full of hunters? Never did occur to us you'd all be so fixated on some incubus theory you wouldn't have found the _real_ demon that killed your people after this long."

"So the fact _this house_ ," protests Chris, who will surely never be accused of giving up too easily, "just so happens to be the home of the daughter of a _known witch_ played no role whatsoever in your decision?"

"You realise that's not actually how the locals down at Beacon Fell introduce the Martin family, right? Did we need more reason than that there was a job opening at a Tower full of hunters, defended by mountain ash?"

Stiles watches the confusion flicker across Chris' face with something that feels horribly like hope now wedged behind those dissolving giggles in his throat. The hunters may not _like_ fae, but that alone won't get them shot on sight. Is it possible – even slightly possible – that Boyd has found an opening to let them talk their way out of this?

The pregnant silence that has descended on the room is broken by footsteps on the stairs, and Chris seizes upon the distraction as his sister reappears at the door. "Kate."

"Did I miss anything fun?" Kate takes them all in with a smile.

"I'll dare to say I've made a few interesting discoveries about our prisoners," Chris allows.

"So did I," says Kate, and produces Lydia's book on demonology from under her arm.

Stiles can only stare, dumbfounded, as Chris takes the book and begins to page through in leisurely fashion. Kate was up and down from Lydia's rooms in almost no longer than it should have taken to climb the stairs. She couldn't have found it so fast. Lydia had those books hidden so well no previous search had turned them up. She would never have made the mistake of leaving a book like that out where it could be found. Could she?

There's no answer from Lydia. She's white as a sheet.

Chris closes the book with some force. "Seize her," he orders.

Lydia takes a step backwards, but she never makes it to the door. Two of the hunters' men intercept her, twist her arms behind her back and force her to her knees on the damp dungeon floor. None of the Argents themselves need move a finger, unless you count the part where Chris moves in to lord his victory over their helpless captive.

"Lydia Martin," he declares, voice low with victory. "I do believe your mother would be _proud_."

* * *

The hunters are far too cautious to lock a witch within reach of three of her alleged 'familiars'. They lock her in the armoury instead, with a man to guard her door.

The hunters are triumphant. Stiles feels ill.

"How the hell did Kate even find that?" he hisses at Scott.

Just how trivial that question is in the big picture doesn't really occur to Stiles until it becomes apparent that _Scott McCall_ , of all people, is giving him the _that's what you're leading with?-_ look. "She _went into Lydia's room_ and _looked_. Stiles, what's going on here? Did you know about this?"

"About how the hunters have been trying to find an excuse to pin 'being born of a witch' on Lydia for the last several years straight? Yeah, I had some warning on that, but..."

"Stiles, _everyone_ knows that!" protests Scott. "I mean about _the book_! Is it really Lydia's? What have you and her been doing? I thought she was just helping you research the volkodlak."

"Okay, yes, the book is hers and there's more going on. It's related to Derek and it's really complicated, but we sorted it out and..."

"And what?" "And I'm sorry I didn't tell you more about it, but this whole thing with me and Derek and Lydia and the hunters is a really long story, and it's all so political and really awkwardly personal that I can't even keep track of what parts I'm _allowed_ to talk to _who_ about anymore, okay? And it shouldn't even have anything to do with this! Not unless this is why Lydia didn't hide her books again properly, which doesn't even-"

" _Stiles_ , calm down." Scott throws a furtive look at the rest of the room. "I don't mean like you have to tell me everything. But _I can't help you_ if I don't know what's going on."

Stiles swallows, tries to blink away a sudden tightness behind his eyes. "Nothing personal, but I think we may be past where _anyone_ can help me. Or Lydia. Jesus, if she's kept this all a secret so long, why would she leave that book where Kate could walk in and find it? And why would Kate-"

"- _be behind you!_ " Scott hisses, giving Stiles barely the time to freeze, open-mouthed, before a hand lands on his shoulder with weight enough to rattle his bones.

"Stiles! Just the man I was looking for," croons Kate. "Got time for a quick word with your Auntie Kate?"

Recovering from the brunt of the blow, Stiles is far too distracted by the possibility that Kate may have heard anything he and Scott had just said to come up a better reply than, "Um, sure, why not."

Beaming, Kate leads him away to a far corner, away from Scott, where she can place herself between Stiles and any convenient exit.

"So!" she says. "I know how distressing this whole day must have been for you, but there's a thing or two you and I should really discuss, don't you think?"

"The volkodlak's real," blurts Stiles, nevermind the odds that _any_ of these vultures are ever really going to want to hear about it. "Whether you trust them or not, they were telling the truth about that werewolf. It was dead long before any of you showed up."

"And we'll take care of it all in due time, don't you worry," Kate assures him, with what is presumably all the condescension she can spare just at the moment, "but what you and I really need to talk just now about is you and Erica."

It takes Stiles a moment to remember that as far as Kate knows, he and Erica are... something. Probably a verb. "Me and Erica."

"I wasn't going to embarrass you by bringing it up in front of the cavalry – you know, my brother is many things, but he can be just a _little_ old-fashioned when it comes to young romance, especially when the supernatural gets involved. If I were you, that's a conversation I'd rather avoid. So, you tell me what I want to know, and Chris never has to hear about it. Deal?"

Stiles has made deals with literal demons he's liked more than this. Kate is clearly enjoying this far, far more than he's comfortable with. There's a twinkle in her eye like the first spark in a wildfire. "What do you want to know?"

"Just your opinion on one little loose end," Kate sneaks a meaningful look at Erica. "Is she a succubus, or is she a fairy? What do you think, Stiles?"

Well. Fair enough. "If she gave me any reason to think she wasn't human, don't you think I'd have told someone?"

"Give your girl some credit, Stilinski: she was never going to make it obvious. But I'm going to bet that you've seen a side of her the rest of us haven't, and hindsight is such a powerful tool for finding meaning that passed us by in the moment. So tell me," Kate by now has drawn so close she's all but whispering directly in his ear, "what's she like in bed?"

Stiles jaw drops. He honestly doesn't know what else he expected, but even from Kate, this is more direct than he'd been remotely prepared for.

"Oh, she'll be good – either way – but just how good?" Kate wonders. "Glamour can make for one hell of a drug, but how far would it carry beneath the surface? Whereas an actual succubus," the noise Kate makes here is neither decent nor transcribable, "Oh, I'm betting _she'll_ give you the kind of night that would bring the saints to depravity. Get her claws into parts of you you never knew you had; wring you out like a used rag and bring you crawling back for more. Am I right?"

"Actually, I'm saving myself for marriage," Stiles manages, somehow.

Kate laughs at him. "Really, Stiles? You think I don't know what goes on in the head of a strapping young man your age? That we don't notice those _urges_ that keep you up at night; that animal of primal lust raising its head for every pretty face to so much as glance your way? Sure, you may _play_ a little hard-to-get, but most of you can hardly keep it in your pants on a good day. It's adorable, really – you may lack finesse, but the enthusiasm alone... you wouldn't let all that go to waste, now, would you, Stiles?" Stiles gropes for a reply, and finds his mind has gone all but utterly blank in self-defence. "What was the question exactly?"

" _Er-i-ca_ ," says Kate, enduing every syllable with lascivious intent. "Or is there something else she likes you to call her?"

"There's really nothing with me and Erica," manages Stiles.

"Is there." Kate looks him quickly up and down, biting at the side of her lip in thought, leaving Stiles suddenly very personally aware of the _real_ risk might be that she'll believe him. "So why is that? Or would one of the others be more your speed?"

An explosion of noise from across the room is his unlikely saviour. Kate whirls to see; from behind her, Stiles gets only a partial view of one of the hunters attempting to physically restrain Jackson in the doorway. More surprising is that the man appears to be having real trouble.

"-to you, I'm _talking_ to that inbred, _mutt_ -bothering _trophy_ hunter who put her there!"

The silence that descends upon the room as Jackson, wild-eyed and furious, shoves the stunned hunter aside, settles like unto the calm before a storm. Chris Argent turns to face him with an exaggerated slowness that promises terrible things.

"Mr. Whittemore. Did you have a complaint to make about the manner of Miss Martin's arrest?"

There's a redness to one side of Jackson's jaw that suggests he's been punched in the fray, but the rawness of his voice betrays only his rage. "You locked up Lydia and _that's_ all you've got to say? What, is it easier to pin your screw-ups on your own _patron_ than it is to have to answer for how it takes you three tries to find one life-sucker and you can't even get that right?"

"Though your loyalty to her name is certainly admirable, forbidden magical texts were found in her possession, Jackson," says Chris. "I would not be doing my duty if I let her go free."

It's hardly an answer aimed to mollify, and Jackson isn't mollified in the least. "I don't fucking _believe_ this! When that demon came through our window, where were you then, huh? When Harris and the maid were having their souls sucked out through their necks, where were you? You have had a goddamn _werewolf_ living under your own roof for months, and _Lydia_ is the one you stick this on?"

The room goes momentarily quiet.

"A werewolf," says Chris, voice quite devoid of feeling as his eyes shift to the boy Jackson had none-too-subtly indicated while voicing that accusation. Scott goes very still, staring at Jackson in horror.

"And you had _no idea_ ," Jackson sneers.

"Jackson!" Allison exclaims, horrified, covering her mouth with her hands only too late to keep that from slipping out.

"Do you have anything to say to that allegation, Mr. McCall?" asks Chris, ignoring both of them as he fits a lever to his crossbow, drawing the string back to the notch with a sickening creak that plays along Stiles' already stretched nerves.

Chris has never liked Scott. Stiles is fairly sure he's loathed Scott since the first day Allison ever smiled at the cute stable-boy who _was not supposed_ to be trying to help out his daughter with a limping horse. And as careful as Scott and Allison have tried to be, there's no way Chris has ever really believed that keeping them apart was as simple as ordering them to stay away. Handed an excuse to be rid of Scott altogether... Chris may not stop to wait for proof at all.

"I didn't..." Scott stammers. "I'm not..."

"Dad, wait," Allison tries. "You don't have to-"

"You know, I always did wonder how you and your little friend kept up with all those chores so easily," Chris adds, fishing a bolt from a pouch.

"Oh, come on!" Kate interjects, striding across the room and plucking the bolt from Chris' ready hand with unlikely ease. Perhaps it helps that Chris seems as surprised by the interruption as the rest of them. "Scott? A wolf? _Really_? Anyone could see there's not a wild bone in this little body, is there, Scotty?" Scott gapes at her with the rest of them as she arrives at his side.

"I'm sure a brief application of _wolfsbane_ will soon put all doubts on the matter to rest," says Chris, the promise of violence in his voice, if anything, only heightened.

"Oh, it'll show he's a were- _something_ ," Kate agrees, patting the side of Scott's face affectionately, even as the look on it returns to panic. "Bitten by an alpha in the dead of the night, nigh upon a twelve-month gone, is that about right, Scott? But you know what they say: the shape you take reflects the person you are, and Scott here – well. Here's a riddle for us all: what do you call a wolf who sleeps peacefully at the foot of your bed every night for a year, who eats the scraps from your own table, who rolls over to have his belly rubbed with a word from his mistress, who'd never hurt a living soul but on your command? What do you call a wolf _tamed_?" Kate actually pinches Scott's cheek for emphasis. Scott himself does not quite manage a nervous smile.

"You're telling me Scott is a were- _dog_?" There is little reassurance in the awareness that Chris seems to find this idea as ludicrous as Stiles does.

"Doesn't quite have the same ring to it, does it?" muses Kate. "Sorry for keeping this one under the rug, big brother, but little Scotty needed some time to prove himself before we could make the announcement."

"...and this... _mistress_?" Chris grits the question out through his teeth. "Should I take her as more than a rhetorical device?"

"Oh, it's not _me_ ," glibs Kate. "By the time I found out about our little puppy, the work was done. Credit for taming this beast goes elsewhere in the family."

"Allison?" asks Chris. It's hardly a question.

Allison swallows visibly. "It's true."

* * *

The elder Argents take their argument to another room. The door is hardly closed before Scott and Allison start their own.

"You told _Kate_?"

"I didn't mean for her to find out, Scott-"

"Why didn't you _tell_ me?"

"I couldn't have covered for you for this long alone," Allison won't raise her voice but she struggles to look at Scott directly. "I couldn't have covered for _us_ without her help. That's all she's done for as long as she's known."

" _How_ long has she known? How _much_ does she know?"

Allison hesitates. "She knows... about us. That we're together. But she won't tell my father that – she's been nothing but supportive, Scott, I _swear_. I didn't tell you because-"

"Because _why_?"

"Because it was easier to keep it separate as much as I still _could_ ," this last is as close to pleading as Allison has come. "Easier to keep her from prying further if she understood that you weren't ready for more attention. That I was the only one we could trust with you."

"You mean easier to get her to keep our secrets if she had one of her own?" argues Scott, unappeased.

Allison looks him briefly in the eye, the frayed state of her nerves clear in every line of her face. "Kate just saved your life, Scott. Even now, she's in there, talking my father down. If we're going to make it out of this, we need every ally we have."

Scott falters and throws a look at Stiles, seeking support. Stiles shrugs back at him. He'd be pretty mad if Allison had gone spreading _his_ secrets to her family too, and he's not even in love with her, but Kate did kind of save their bacon back there. And it's certainly not Allison's fault that Jackson's in on the secret. Or that Jackson's the kind of headcase who'd blurt it all out to make some kind of point.

Scott shakes himself. "Allison, just what does Kate think is going on between you and me? All that stuff about _taming_..."

"She thinks _you're_ worth saving, and _I_ deserve the chance to help you prove that!" Allison snaps, before checking herself. "I'm sorry I didn't tell you. But I needed her to believe that my loyalty to my family came first."

"Does it?" asks Scott.

Allison folds her arms. "Did you know about Erica and Isaac?"

"I... that's not..."

"Yeah," says Allison. "That's what I thought."

"Oookay," Stiles says quickly, before round two can begin, "How about we put a hold on this one subject until our lives aren't actively blowing up in our faces, huh? Who's with me?"

Scott and Allison look away, embarrassed.

"Do you really think Kate can talk him down?" Scott asks, quietly.

Allison nods. "I think she's probably talked him down already. By now, he'll be down to arguing about principles and obligations. I should probably look in on them though." She glances guiltily toward the door.

"I should talk to Jackson," says Scott. Allison nods again and begins to turn away.

Scott catches her by the sleeve. "Sorry," he offers. "I know you were only trying to do what's right."

Allison gives him a thin smile. "I'm sorry too."

"So... Jackson?" Stiles offers, after several seconds have passed without Scott having moved. He vaguely hopes that 'talk' is a euphemism for something more physically painful. Wherever he's got to, the guy has a lot to answer for. "Where _is_ Jackson?"

"He's..." Scott concentrates, listening, then frowns. "He's in the armoury?"

"What?" says Stiles.

The reverberating sound of a hunter's horn rings briefly down through the Tower, before stuttering abruptly out.

"What was that?" asks Stiles.

"It came from upstairs," says Allison.

The door to the hunters' quarters bangs open, Chris behind it. "Stay here!" he barks at the three of them, then makes for the stairs at a run, Kate behind him.

It more or less goes without saying that no-one stays there.

Upstairs, probably-Ben is slouched against the wall outside the armoury, horn held weakly in his hand, dazed but living. Blood oozes from a gash in the side of his head, beginning to drip past the line of his jaw – an injury suggesting a blunt impact of some force. The armoury door is open.

Jackson's wooden training sword lies abandoned just inside the door. They also find Jackson.

"You," growls Chris.

"Me," agrees Jackson, quite unashamed.

"Where is she?"

"Gone."

"You will answer for this," Chris promises.

"What can I say? She probably _bewitched_ me," Jackson sneers.

Chris ignores him. "She'll make for the stables. If we can't intercept her there, we'll catch her on the road."

"Why wait?" calls Kate, crossbow in hand. She's standing by a window in the hall, eyes fixed on something down below. The window isn't wide and Stiles' angle is terrible, but around Kate's body he glimpses a cloaked figure hurrying across the courtyard in the last fading light of dusk.

Stiles wasn't in the Tower on the day Lydia's mother had fled for her life; neither he nor anyone else who would ever admit to the fact had been there to see her leave. Even so, the idea of her poised on the very steps of the Tower in the moment of her flight has been an image lodged in Stiles' mind ever since the news reached him, fanciful though it may be; one which came back to him again and again in the years that followed as he tried to make sense of the event. It comes back to him again now, watching Lydia follow in her mother's footsteps. He's never imagined it a scene he'd see for real one day.

Only Lydia isn't going to be allowed to make it away.

"How alive do we need her?" Kate asks, loading her crossbow.

"Your own discretion. Any shot that stops her," Chris replies.

"You can't just-" cries Stiles.

Chris blocks his way. " _None_ of you will interfere."

"Dad, please..." Allison tries.

"This is not the moment to try my patience, Allison," Chris warns, eyes barely flickering to Scott. "Our conversation about your... _associations_ is not over."

Scott looks torn. Then he looks like he's listening.

Kate loads her crossbow and steadies it on the window-sill.

It occurs to Stiles that the sound he's hearing might be wing beats.

A moving shadow drops across the window, grabs the crossbow and wrenches it out of Kate's hands, the bolt launching harmlessly off into the distance. The attacker is gone again so fast that for a long moment, Stiles is honestly not what he just saw.

Derek doesn't leave them wondering. He soars back into view with teeth bared and wings spread, working to hold himself aloft as he lets out a deafening roar. The dying light casts his skin in black and grey, but his eyes burn like glowing coals, fearless in their defiance. Stiles' heart clenches at the sight of him. Never in all their hours together has he seen Derek so exposed as this, magnificent and terrifying as he shows the hunters precisely who and what they've angered.

Then he folds his wings and swoops low, plucking Lydia's cloaked figure from the ground before vanishing around the Tower out of sight.

Kate recovers first. "Well, that's one question answered," she murmurs, turning to Chris. "That was him. The first that attacked me."

Chris balls his hands into fists. "They won't get far. Not by air, an extra human body will be more weight than it can carry. If we can find their trail... this could be our chance for both birds with one stone. We'll need to split up, we can cover more ground. You-"

"-go after a witch and a demon without backup, leaving three more unguarded back home, with this rabble?" Kate's voice drips with scorn. "Hm, now what could possibly go wrong?"

"Do you have a better idea?"

"Leave the guards. You, me, Allison – we'll only need one party. We'll find their trail in no time. After all, we've got a better way to track her on our side." She inclines her head at something just over Stiles' shoulder. "Scott. We can trust you, right?"

"Me?" Scott clearly hasn't been expecting this any more than Stiles, who himself just about did a double take.

"This is your big chance, Scott," Kate tells him, with the half-smile of someone aiming for no less than _three_ birds with one stone. "They say a werewolf can hear a twig snap a mile away. Can follow a trail so faint even a trained bloodhound would miss it. You won't get a better chance to prove yourself."

"You want me to help you find Lydia and D – the demon?" Scott sounds incredulous.

"What do you say, Scott?" asks Chris, obviously intrigued by the chance to put Scott to the test.

Scott stares at him mutely. Allison looks back and forth between Scott and her family, and seems to make a decision.

"He will," she says, taking Scott's hand. "You can trust him. I'll stake my own word on it."

**Notes for the Chapter:**

> Though chapter 15 isn't quite done yet, you can see a little of Lydia POV immediately following these events [in this side story](http://archiveofourown.org/works/3638256/chapters/10081664).


	15. Chapter 15

**Notes for the Chapter:**

> Couple of indirect references in this one to events covered in [the prequel chapter](http://archiveofourown.org/works/816932), though it still shouldn't be essential reading to follow the gist of things here. 
> 
> Also, in case you missed it, one more missing scene featuring Lydia and Derek set between this and the last chapter [went up as a side story](http://archiveofourown.org/works/3638256/chapters/10081664) recently too.

"If I'm going to help you," says Scott, watching Chris and Kate bark orders to their men as they assemble a horrifying array of gear for the hunt, "I have a condition."

Having remained wholly mute as Allison accepted Kate's terms on his behalf, then having followed the Argents back down here in a stunned silence, Scott's resolve has perhaps been slow to harden. If Stiles knows Scott at all, it won't have been wasted time.

Chris and Kate themselves would likely have preferred their bloodhound not to find his tongue at all. Only grudgingly do either of the senior hunters grant him their attention.

Scott licks his lips, nervous. "If we find Lydia, you take her alive," he pronounces. "Agreed?"

The flash of displeasure that briefly mars Chris' features requires no werewolf senses to interpret.

"Please don't test his loyalty," says Allison, quickly. "That includes his loyalty to Lydia."

"Far be it from us to test a beta's loyalty to his _alpha_ ," says Kate, shooting her brother a meaningful look. Chris grinds his teeth, but he also appears to have found some sense in his sister's perspective.

"Alright, Scott," he declares. "If you help us find Lydia, we'll bring her home alive if we possibly can."

Had anything passed between Scott and Chris then, it might have burst into flame.

Stiles swallows thickly and makes a stab at thinking like a hunter. People like Chris and Kate make their knowledge of lycanthropes a matter of pride. Every Argent would have learnt from the cradle that the fastest way to get a werewolf to take a new alpha is to kill the old one – and any member of his pack who disagrees.

Derek and his ilk may be able to make a deal that will hold a man to his word as long as they both shall live, but all a werewolf can do is hear his enemy's lie.

"Scott, a quick word with you before you go?" Stiles hisses to him, low and urgent.

Scott tears his eyes away from Chris and mutters a quiet assent. The hunters are mercifully good enough to leave them to huddle in the limited privacy of the nearest corridor alcove.

"You know the moment you find Lydia, they're going to use any excuse to shoot her in the back while she runs," Stiles whispers, without preamble.

"I _know_ ," Scott agrees. If Stiles had needed any further proof of just how bad things have become, the cold acceptance in Scott's face speaks volumes. "But Allison's right: they're not going to let me out of this. At least if I'm out there with them when they find Lydia, I can put myselfin the way."

" _Scott_ ," says Stiles. "Scott, we talked about you walking out _in front of arrows_. They're not going to hesitate to shoot you just because-"

"They will if _Allison's_ there with me. And it may not even come to that! I can do more out there than I can here. Besides, this way I can at least buy _you_ some time!"

Stiles blinks at him, suddenly lost. "Buy me time for what?"

"For you to get Derek and the others out of this!" Scott hisses, throwing a furtive look back into the room.

Stiles feels horribly as though he's lost control of this conversation. Also rather numb. "How exactly am I supposed to do that?"

"I don't know. You'll think of something, right?"

"When did this become _my_ job?" Stiles protests desperately.

Scott looks at him like he's gone crazy. "Because it's what you _do_? You've been the only one with any idea how to get us all through this alive since the day the first incubus came after Lydia!"

If Scott's expectations had been burden enough, this sudden show of faith weighs heavier still. "So we're ignoring the part where the upshot of all my great ideas is this mess we're in now?"

Scott makes a face, the sort made by the terminally good-natured when someone has just mortally insulted their very best friend. "Stiles, this isn't your fault. And even if _some_ of it is... look, you can't worry about that now."

"Now _there's_ a good argument."

"I mean it! And if you really think it was your ideas that got us into this, then what you need to focus on is finding the way to make it right!"

"Scott," Chris' voice cuts into their conversation with some force. Scott and Stiles leapt apart as if stung.

"They're waiting for you outside with the horses," says Chris.

Scott nods and takes a step toward the door. "Aren't you coming?" he asks when Chris makes no move to follow him.

"In a moment," Chris replies. "Oh, and Scott: you should know, we can't spare a horse for you tonight. You'll be on foot. I hope that won't be a problem."

Few more blatant lies than 'we can't spare a horse' have ever passed Chris' lips in Stiles' hearing. Of the six mounted hunters who arrived home before sunset, only three are about to set out again. Even Scott could do the maths on this one.

"That's fine," says Scott, refusing to rise to the bait. "I can track more easily on foot anyway."

"Good to know," says Chris.

Scott gives Stiles one last, desperate look, then turns and hurries away. Chris watches him go. The look he turns on Stiles suggests he's feeling very little rush to follow. "I hope you haven't been advising your friend to do anything that might get him into trouble."

"Like what?" Stiles really does not have Scott's apparently bottomless well of patience with Allison's relatives. "Tracking a demon and a witch into the woods at night with a bunch of hunters?"

A twitch at the corner of Chris' mouth suggests less amusement at Stiles' wit than bemusement that Stiles feels he's in any position for levity. That Scott isn't the only member of the Tower's staff whom Chris has decided he needs to reassess in the light of recent revelations is beginning to make itself apparent. "I suppose you think keeping your friend's secret is something to be proud of," Chris observes, in that deceptively casual tone he favours. "No easy task, teaching a newly bitten omega to curb his instincts."

Unbidden, the chilling terror that had been the night of Scott's first full moon comes back to Stiles, visceral enough that it's an effort not to shiver. Following Scott out into the woods in the cold, not knowing what he'd do if he found him, knowing only that if the hunters found him first... There'd been moments – minutes, even – when he'd been unable to imagine any scenario where he, Scott and Allison all made it to morning alive. But Scott had surprised them. Or maybe they'd all surprised each other.

Like hell if Chris Argent has the right to know the least of that. "Lucky for Scott, I'm not a hunter. He's never hurt anyone."

"Never?" Chris echoes.

"He ripped a volkodlak's head off in front of me once. Does that count? Not that that stopped it from _coming back_."

"Ah," says Chris. "Our prisoners' fantasy assailant. With appetites as well suited to cover for the presence of a nest of incubi as anyone could ask for. Convenient, that it should show up here."

The ease with which Chris can just reason it all away makes Stiles feel physically ill. How many teeth the volkodlak will have to get into him or his sister before they believe it exists he can't even guess anymore. "You know," he hears himself say. "Allison told me once you used to have a code. You aren't supposed to kill a werewolf if he's never taken human life."

That one gets an actual wry smile out of Chris – far more distinct than the lip twitch from earlier, though scarcely less patronising. "You think the world at large would be happier if we waited until every young werewolf had taken at least one human life before taking action?"

"Seems to work with humans."

"If you still think werewolves are no different from us now, I'm going to have to reassess how much time you must have spent with Scott since he was turned."

"Maybe _you_ need to spend more time with werewolves you aren't trying to kill."

The stare Chris gives him on the tail of this remark goes on rather too long for comfort before Chris finally looks away and returns to his gear and whatever last minute preparations he supposedly stayed back for.

"You know, I had a friend once who was bitten," he says, pulling on his coat. "He actually thought he could master the change. Overcome the bloodlust. You'd think a hunter would understand what that entailed – a man who'd spent his life on the trail of the beast – that he'd know his own strength a little better."

"Maybe it wasn't the beast the bloodlust was coming from," says Stiles, in no particular mood for another of Chris' stories.

"You're not wholly wrong," Chris allows. "It was no accident my friend was bitten. He sought it out."

Having heard enough of these sorts of hunters tales over the years to feel he knows the rhythm, this is something of a departure from the usual script. "...what?"

"You can't see the appeal?" asks Chris. "The strength, the stamina, immunity to illness? In the wrong hands familiarity breeds the worst kind of contempt. A man starts to believe that if he's fought the wolf and won in the field, he can fight it and win in here too." Chris taps the side of his head. "He starts to think he has a right to that kind of power. Sad to say there are some mistakes it seems every generation has to make anew for themselves. It never ends well."

Inexperienced hunters who make some elementary mistake and pay for it are a regular feature of Chris' parables from the field. _Experienced_ hunters succumbing to _this_ sort of ordinary human failing, not so much, but Stiles is far too angry with Chris just now to be in any condition to make sense out of this strange new fable. "Does this have something to do with Scott?"

"There's nothing harmless about what Scott represents," says Chris. "Most rules exist for a reason."

"Then how come the old rule on werewolves is still in the books?" Stiles counters. 

"Chris!" hollers Kate, voice coming from outside. "Are you coming or are we going without you?"

"On my way," Chris calls back, conveniently saved from having to come up with an answer to Stiles' question. Shouldering his bag, he gives Stiles one last, pointed look. "I hope you're not planning anything that might get yourself into trouble either," he declares, and turns to go before Stiles can come up with any sort of suitable retort.

Soon, the sound of hoof beats in the courtyard rises and fades away.

Stiles shakes himself and sets about putting together a plan to get himself into more trouble than the likes of Chris Argent could ever dream up. Scott's little motivational speech really has nothing on the power of raw spite.

* * *

There's a hunter standing by the doorway of the dungeons. He watches Stiles with the expression of a man who'd been warned to expect him, and not on good behaviour. Stiles twitches a little and almost certainly fails at acting casual.

"Aren't there supposed to be two of you guarding the prisoners?" he tries, conversationally.

The man jerks his head towards the upper floors. "He'll be back when he's done upstairs. Argent said Bennett took a blow to the head."

"Did they mention the part where the guy that _gave_ him the blow to the head is still up there too?"

The man stares at Stiles like Scott listening for a heartbeat. Then he swears and goes for the stairs at a run.

Stiles congratulates himself quietly and slips into the dungeons.

" _Please_ tell me you can work your door trick on this thing," he says to Boyd, hurrying up to the door to his cell, the key to the hunters' chest still heavy in his pocket.

Boyd looks at him as though Stiles had asked him to pull a rabbit out of his shoe. "It's _iron_ ," he says, as if counting off points on his fingers, "and it's hardly even a proper door."

"What, it's got hinges! It's got a lock! What more do you want?"

"Come over here and let me punch you through it, then ask me again. Did I mention the _iron_?"

" _Stiles_ ," Erica calls, beckoning him over.

Giving up on Boyd, Stiles goes.

"You need to get to Derek," Erica tells him. "You need to find him before the hunters do."

"He needs to know what's happening here," adds Isaac.

Stiles' first instinct is to protest. The last he saw of Derek, he'd all but dared the hunters to come after him. He certainly hadn't seemed all that interested in anything Stiles had to say, though circumstances have evolved fairly significantly since. Furthermore, Derek's record tends to speak against him on the sort of decisions he makes when left to his own devices. This is a poor time for any of them to be working at cross-purposes

"How am I supposed to find him?" he asks.

"We can tell you where to look," says Isaac.

Isaac's meaning takes a moment to click. "He told you where he'd be?" If Derek's voluntarily spoken to _anyone_ – by whatever means, mystical or otherwise – that's got to be a good sign, right?

Isaac nods.

And that is how Stiles finds himself tearing out into the woods into the rapidly deepening night, hoping against hope that Scott's promise to 'buy him some time' pans out. If it _doesn't_ , Stiles is under no illusions of what's likely to happen if the hunters and Derek find each other first. His accursedly vivid imagination is no ally on this one, and while the hunters may be labouring under the assumption that Derek's primary objective is to get his mistress to safety or to lure them out into the dark, Stiles suffers from no confusion that Lydia is in any way Derek's mistress. Whether Derek intends it or not, she may, in fact, be effectively little more than _bait_.

For all that he's still largely in the dark about Derek's angle, it's hard to read his performance outside the Tower window as anything less than an open challenge. This time yesterday he might have been confident it was all bluff – even a few short hours ago, he'd been able to convince himself that Derek probably wasn't _really_ flying away to murder the first hunter in sight. But that was all before the hunters locked Derek's cohorts away in the dungeons and handed him every excuse his forebear's grisly death may have lacked. Before he flew by to rescue Lydia and announcehimself. Now Stiles doesn't know what to believe.

He knows Scott will protect Lydia with his life, and Derek with, well – he'll _try_ to protect Derek, if only for Stiles' sake. But if Stiles knows Scott at all, he'll also be trying to protect the hunters from _Derek_ , if it comes to that – for Allison's sake if not their own. If the true purpose of Derek's little demonstration outside the Tower really was to lure the hunters out of safety, into the dark of the wilds ...

No-one in the woods tonight is ignorant about where this is likely to go. Chris and Kate didn't bring Scott along only as a tracker – they brought him as muscle too.

Stiles may be sure that Scott won't hurt Derek if he doesn't have to, but he only wishes he was sure Derek's going to give Scott that choice.

It's ample motivation to send him barrelling out into the woods as if all the hounds of hell are on his heels.

Two minutes and the abrupt encounter with one bush, two low-hanging branches and the mother of all spider-webs later, Stiles is developing a new appreciation for why charging around in the woods at night might be a job best left to the professionals. Not bringing a torch may have made good sense in that any light would be as good as a beacon to bring the hunters to his side. That said, it's quite possible that the fact that mere humans might have trouble navigating in the dark is the sort of detail that might have escaped the likes of Erica and Isaac in their rush to send him out here.

He may in fact already be more than a little lost.

What _was_ his plan when he started out here? Head in roughly the right direction and hope Derek and Lydia find him? Assuming Derek is even looking for him. Isaac was a little hazy on some of those specifics.

Stiles mentally makes a quick calculation of how long it's taken the volkodlak to find itself new bodies in the past. Surely well above twenty-four hours at the minimum. Not that they know for sure how long it typically spends staggering around the wilds in its new skin before making its presence known.

The back of Stiles' neck begins to prickle.

This, at least, is relatively easily solved by fishing a small pine-cone out of the back of his tunic.

The night is mercifully clear, and the moon has had the goodness to rise early, but when Stiles looks back over his shoulder, he finds the Tower quite obscured behind a copse of tall pines rising from the ground a short way up-slope. Maybe he should try retracing his steps, at least far enough to put himself in sight of some sort of useful local landmark.

Unfortunately, Stiles' recent steps almost immediately prove to have been booby-trapped by the placement of a fallen branch, which interrupts his stride at precisely the right point to trip him forward over his feet. Ever the master of grace under pressure, Stiles deals with this by yelping and flailing frantically as he topples.

That his flailing hands actually findsome suitably placed prop in mid-air on which to catch his weight is a stroke of inestimable fortune. That this same prop closes a grip around his arm and forcibly tugs him back onto his feet is one more surprise than Stiles is ready for. He yelps again, putting events in order in his head only when the soft sound of Derek shushing him quietly reaches his ears.

"Stiles? Which way do you think you're going?"

"Derek?" Circumstances render the faint glow of Derek's eyes uncharacteristically welcoming. "Go on, mock the guy without magic night-vision. What's the big idea creeping up on me?"

"Excuse me for taking the time to make sure it was you." The casual ire in Derek's voice is music to Stiles' ears.

"Is Lydia with you?"

"She's back up the hill. Come on." Derek's hand finds Stiles' easily, tugging him into following.

The need to ask _does this mean you're not mad at me anymore for calling your rape-and-murder-happy ancestor crazy? –_ or possibly even _does this greeting mean you_ aren't _luring the hunters out here to pick them off one by one? –_ bubbles quietly away in Stiles' chest. Any way he turns the inquiry in his head comes out sounding fairly undiplomatic, but few have ever accused Stiles of knowing when to keep his mouth shut. This is perhaps why what actually comes out is, "'Come on' – that's it, 'come on'?"

Derek stops short. "What exactly do you want from me Stiles?"

Stiles' need for answers to a million inappropriate questions stutters out. Derek doesn't sound angry. He sounds exhausted.

"I – sorry," Stiles mutters. "I don't know what... it's just been a really long day, okay?"

Derek squeezes his hand gently. "It's not over yet." He starts back up the slope again.

A dark blob detaches from one of the nearer pines when they get close. Stiles can't make much out in the moonlight, but Derek greets it with, "Found him."

"Lydia?" asks Stiles, feeling faintly ridiculous.

Stiles finds himself being suddenly and tightly hugged by someone he can't quite see, though almost as quickly as it happens it's over again.

"Good of you to join us," says Lydia, her voice suggesting a level of composure somewhat at odds with the fact she just embraced a lowly servant boy.

"What do we have waiting for us back at your Tower?" Derek asks.

Oh – right. Stiles is theoretically here to share information. "Chris and Kate have Scottout hunting for you. Jackson blurted out his secret in front of everyone and-"

"I _know_ , Stiles," Derek cuts in. "Scott's leading them away from us. I flew one of Lydia's scarves out to the edge of the river. They won't be able to fault him for following that trail, and it should take them hours to get there on foot."

"...oh. Okay." This is a far simpler solution than anything Stiles had been picturing.

"You don't have to worry about Scott. He's on board. He knows where he's taking them."

"How... oh, _werewolf hearing_. And _demon_ hearing. Nice trick," says Stiles, weakly. Why did he even need to come out here again?

"The Tower, Stiles," Derek reminds him.

Right. "They left three hunters behind. One of them has a concussion – you can thank Jackson for that – he shouldn't be up and about much. The other two are guarding the dungeon. They're not supposed to move until the Argents get back to relieve them."

A flash of white teeth is briefly visible in the moonlight as Derek grins. "No succubus ever to be guarded by a single man," he says, wryly, sounding like he's quoting something. "They do learn, eventually. Alright. We can work with this."

"So we're springing them out of there?"

"If all goes well," says Derek, voice falling ominously low. "But we have a detour to make first. Isaac and Erica aren't the only kin I have waiting for me there."

It takes Stiles a moment to catch on. "You mean _him_? Derek, he's _dead!_ "

"He's much worse than dead," says Derek. "There's a ritual: Lydia and I have already talked it over. We can summon his spirit from the skull of his last true body."

"Did you forget the part where we don't _have_ his skull?"

" _I_ have it," says Lydia.

Stiles stares at her with an expression that is sadly completely lost on her in the gloom. "You..."

"What?" asks Lydia, defensive. "Did you think I'd leave something as dangerous as a demon skull lying around for anyone to find? Do you _know_ how many different rituals they can be used for?"

Stiles rubs his temples. He'd had all day, and it had never even occurred to him to _ask_.

"Are we done talking about this?" asks Derek, impatient.

"Wait," Stiles for one is not done talking about this. He feels completely at sea with this plan, "do you really have to do this _now_?"

" _Yes_ , now!" Derek snaps, then sighs, and seems to take some sort of pity on Stiles' inability to psychically divine whatever details of the plan he's missing. "He isn't dead. Not properly. Something's holding him here. Do you think it was an accident, his coming here?"

That Lydia's mother must have been the witch responsible for the foiled attempt to save Laura's mentor's life is so obvious to Stiles that he can't immediately remember for sure whether anyone's said it out loud yet. That he's the same spirit animating the volkodlak is surely just as apparent to both of them. "Well, no, but-"

"Before the witch put him to sleep, she sealed his soul outside his body," Derek goes on. "You know enough to know what that means: even now, he's still anchored to somethingshe left behind. That's why he's been able to reanimate body after body, lashing out at anyone he can reach while the Tower is closed to him. The only way to put an end to this is to find whatever's holding him here and destroy it."

"And the fastest way to do that, unfortunately," adds Lydia, "is to ask him."

"And then?" Stiles asks with a sinking feeling.

"We destroy the tether," Derek replies, "free the others and run. We're all in danger as long as the hunters remember our faces. We won't be coming back here again. This needs to be finished _tonight_ , while they're still distracted."

The finality of Derek's words hit Stiles with a force that almost knocks the air out of him. In all the time he's spent bargaining with fate over the last few hours – swearing _just let us all get out of this alive and it doesn't matter if I never see Derek again –_ the real plausibility of his own terms hadn't quite sunk in until he'd heard Derek echoing them back to him, almost word for word. With a tightness in his throat, Stiles kicks himself internally for his own hypocrisy. He doesn't get to complain. He broke the bond between them precisely so Derek could leave if he wanted to. It hardly matters now that only days ago, Derek's answer had been a promise to stay. The stakes have changed irrevocably since then.

"Okay," he says aloud, steeling himself already for this one last burst. "Okay. Let's do this."

* * *

There are no lights in the windows of the Tower when they arrive at its foot.

"I'm guessing the front door is going to be a little obvious?" says Stiles, who already has a prickly feeling how this is going to go.

"Everything we need is in my room," says Lydia.

Derek nods, distracted, eyes fixed on the distant window of Lydia's bedchamber, several floors above. "I can probably get you both up to the window if you go one at a time."

" _Probably_?"

"Hauling humans up and down walls isn't something I make a habit of," replies Derek, testily. "Who's going first?"

* * *

Stiles doesn't know whether to be relieved or the opposite when he discovers that Derek doesn't intend to fly them up there. "You're going to _climb_?"

"I can either take off silently _or_ I can do it carrying two hundred pounds of extra weight. Climbing is easier," Derek explains, with the sort of terse frustration with Stiles' stupid questions that belongs in simpler times. "Feel free to shut your eyes if that's what works for you. Now hang on. I'm going to need my hands."

So Stiles wraps his arms around Derek's neck, and his legs around Derek's waist, and holds on for all he's worth as Derek steps up to the wall, sets his claws deep into some invisible crack in the masonry, and begins to climb.

Derek goes up the side of the Tower like a spider, flattened against the side of the building with all six limbs spread, wing-claws digging in at either side for extra leverage. Wrapped around his torso and clinging for dear life, Stiles is acutely aware of virtually every working muscle in Derek's body, to say nothing of the effect of his own weight on Derek's fragile balance through every other movement. The outer Tower wall is hardly mirror-smooth; years of wind and weather have stripped at its construction with an uneven hand, wearing channels in the mortar and peeling stone from stone. How Derek can tell which exposed bricks and crevices he can trust with his weight from those that will crumble under him Stiles prefers not to think. Closing his eyes doesn't really help though, not when it makes the next lurch upward that much harder to predict. If Derek hadn't told him outright that this was the easier way to get him up, Stiles would never have believed it. He's seriously contemplating telling Derek to _find a lower window and we'll take the damn stairs_ when Derek's weight tips suddenly forward. For a stomach-lurching moment Stiles half-believes they've fallen off, before it comes to him that they've arrived.

Derek steps down onto the floor of what must be Lydia's room, and disentangles Stiles' vice-grip on his midsection with a reasonable approximation of dignity.

Stiles looks up at the sky outside through the window, trying to find the words to make _that thing you did where you got us both through that tiny window without banging a single elbow on anything was really impressive_ sound like a rational sort of observation.

Derek rolls his shoulders and stretches in the sort of furiously sexy way he does nearly everything, then vanishes back out the window again. It takes him a few minutes more to return with Lydia (who hisses and makes several not-terribly-ladylike comments as she's likewise deposited on the floor), then put his demonic night-vision to some good use finding them a candle and some flint.

"Well," says Lydia, dusting herself off. "Shall we get started?"

* * *

Along with her books and coloured chalk and other paraphernalia, Lydia produces a blackened demon skull, cloven down the centre into two pieces. "The hunters aren't so foolish as to leave a dangerous magical object lying around in one piece. Fortunately for our purposes, it doesn't need to be."

"How long will this take?" Derek asks.

"You don't rush magic circles," Lydia proclaims. "They need to be precise. A few drops of your blood should serve as a catalyst."

Mention of the hunters stirs something worrying out of Stiles' jumbled thoughts. "Isn't the spell for this going to be in the same book Kate got hold of?" They don't have Boyd on hand now to get them easy access to the hunters' quarters. The whole point of sneaking themselves upstairs without raising the alarm is going to go to waste if a vital piece of equipment is stuck on the ground floor.

"Yes, but since we don't _have_ that, I'll have to do it from memory," says Lydia, as though this poses no particular difficulty.

"From memory?" Stiles is quite sure this isn't a spell Lydia has done before. "Are you sure?"

Lydia rolls her eyes. "Stiles, this spell requires a perfectly standard Solomonic circle, with a triangular focus in the place of the inverted septagram you'd remember from our binding experiments, with elliptical correction for inauspicious phase of the moon. The basic outline _and_ the standard form of the ritual is repeated a dozen times over in my mother's notes. We have a subject bound to this plane of existence, his physical skull as a focus, and Derek can tell us his true name. I will never in my life have an easier invocation than this. You and I created new magic out of raw theory not one week gone. _I can do this_."

Stiles raises his hands and backs away. Clearly this is the time to stand back and let the woman work. Somewhere in there, Stiles may also have missed his chance to check how Lydia feels about raising the spirit of the same demon who tried to rape and murder her back in midwinter too. He's certainly not going to try bringing that one up now.

"I can see why it was her you went to for help," observes Derek, bemused.

"I'm starting to see why the hunters never believed she wasn't really doing magic after ten years of spot-checks," Stiles grumbles, perhaps unkindly.

"I heard that," calls Lydia, and throws a piece of chalk at his head. "Just for that, you're on rune duty. Don't think I won't be checking your work."

* * *

Even though Lydia makes him redo his runes twice before she's happy with them, Stiles is soon glad to have something to do. Lydia's candles have burnt down some way by the time she's satisfied with the completed circle. Even occupied, it's hard enough not to wonder how long their fool's errand will really keep the hunters busy; whether Derek's estimate of the hours they'd have to work was really so apt.

Finally, Lydia stands, admiring her work with an air of some satisfaction, then hands Derek a tiny, silver dagger. "One drop of blood into the flame of each candle, counter-clockwise from the north."

"And then?" Derek asks, taking the dagger and pricking a finger.

"Then you stand on the white cross," Lydia indicates a marking outside the circle, "and call his name."

"Just his name?"

"Feel free to embellish if the need strikes you. Or not," Lydia shrugs.

"Do we need to...?" Stiles starts to ask, until Lydia gives him a look. "Stand here, stay quiet, okay," Stiles concludes, rocking on his heels a little. Okay.

At the nearest edge of the circle, a drop of dark blood falls from Derek's finger to the candle below. The flame fizzles and spits on contact but survives unextinguished, now burning a dark, rich red . The buzz of magic hits Stiles like a gust of wind, prickling goosebumps out of his arms, familiar and strange all at once.

Safe to say it's working, at least.

When Derek reaches the second candle the room dims considerably, the dull red flames a poor substitute for the bright orange that came before. The hum of magic this time passes through him with a lasting chill like the echo of a scream. Stiles looks at Lydia in confusion, almost asks aloud, _did you feel that?_ Watching her do magic has never been like this before.

He only hopes the hunters downstairs aren't near enough to be feeling this too.

The lines of the circle have begun to glow with a cold, white light as Derek comes to stand as directed. When he speaks, though, the name comes out almost as a question: "Peter?"

The candles flicker, casting strange rippling shadows off the two pieces of skull that sit, propped together, at the centre of the circle. Outside, or perhaps somewhere further away, Stiles thinks he hears the wind pick up into a sudden howl, even as a carpet of what seems like thin mist comes rushing inwards between the candles, coalescing where it touches bone into a thin pillar of steam. Stiles is half-convinced he sees the skull itself arc upwards off the floor.

The room goes suddenly, horribly dark.


	16. Chapter 16

There's a figure standing in the shadow of the circle, lit as if by weak moonlight, looking down at its hands.

"Hm," says the spirit. "Now this _is_ unexpected." It looks up.

Stiles had been expecting to see a demon, assuming the spell gave them any distinct visual proof of their success at all. What he sees instead is... well, he supposes that must be _Peter_. The figure in the circle is as human as Isaac and Erica on any day in the Tower, or as Derek had been on the first day of the fair – older, certainly, but not _old_. This spectre of his living self has had its features stripped of colour, but he appears nonetheless in good health, his hair is neat and well-groomed, his clothing clean and unremarkable. He's actually, to Stiles' mild horror, quite as effortlessly attractive as every other incubus he's ever met – more comfortable in his own skin than the unlucky human soul born to it could have ever been.

"Derek? Well, as I live and breathe." The spectre laughs, short and unkind, and sighs lightly, shaking its head at its own choice of words. "It is so hard to give up those little turns of phrase."

"Peter," says Derek, softly.

"How long has it been, do tell me? It's so _difficult_ to mark the passage of time from one's own tomb." Peter's tone drips with condescension. "Some years, obviously, unless... you know, I almost seem to recall our paths might have crossed more _recently_ than that."

The red glow of the candles is far too dim for Stiles to make out the subtle signs of Derek grinding his teeth, but the brief silence before his reply speaks volumes. "What do you want me to say, Peter?"

"Oh, I don't want excuses from you, Derek. After all, in the heat of the moment, I can't say I recognised you myself! It's quite remarkable how death focuses the mind once it all slips away." Peter sniffs, examining the translucent state of his own hands with some curiosity. "Though I suppose being unable to leave the place of the event might influence one's perspective some."

"That's what I'm trying to fix," says Derek, latching onto the opening. "I need to know how-"

"But where are your manners?" Peter protests. "Aren't you going to introduce me to your young friends? Oh, excuse me, I do believe I'm already acquainted with thisyoung lady – _the_ Miss Lydia Martin, I presume? Such a shame our time together was cut so sadly short ..." If Peter's human face had come as a surprise, there's something unpleasantly familiar about the leer he turns on Lydia, and recognition turns Stiles' stomach. Lydia stiffens but refuses to look away.

" _Peter_ ," Derek warns.

"And _this_ must be _Stiles_."

Even knowing objectively that Peter is but a phantom that cannot leave his circle, it takes a genuine effort to follow Lydia's example and resist the need to shrink away from that gaze.

"And you wonder why I didn't know you," Derek mutters, though loud enough to be heard.

"Why, Derek? Don't you think she's my type?"

"You taught us better than this, Peter," says Derek, quietly.

"And here I'd begun to think my brief years in your life must have left little impression on you after all," says Peter, his scorn reaching depths of almost theatrical exaggeration.

It's Derek's turn, again, to stiffen where he stands. "I thought you didn't want my excuses."

"Don't think I _blame_ you for this, Derek. How could I? You can't blame someone for a tragedy so magnificent – you can but _marvel_. The two of us coming to one another's throats in vengeance for the same death, after all those years she put to saving me – all so I could live long enough to witness her end, then die at the hands of my own grieving kin. Why, what can you do but stand and admire the _poetry_ of it all!"

It comes to Stiles, watching Peter expound on his misfortunes as if savouring every word, that the man he's looking at is quite, quite mad.

A voice in his head – one that sounds a little like Scott's, and a little like his Dad's – suggests he might want to consider how anyone could survive the half of what Peter's been through without going mad in self-defence. Peter must logically have a right to as much. It's not a terribly comforting perspective.

"How _do_ you like the role of the tragic hero?" Peter continues. "You know, I think it suits you. And how do you like me as the wailing ghost, the plague of misfortunes that hounds the young master until the truth can at last be revealed?"

Derek stirs slowly, as if lost in some reverie. "I know there's no undoing what's been done to you," he says, his words heavy with regret. "But we called you here because we need to make this right."

Peter tilts his head, seeming to take great interest in whatever Derek might be offering. "And how do you propose to do that?"

"We know Lady Martin was the witch Laura had bind you and put you to sleep. We know whatever she bound you to is still in the Tower. We just don't know what it was."

"Did you figure all that out for yourselves?" Peter laughs, greatly entertained. "How marvellous! How long did that take you, do tell me? I'm sure you don't need _my_ help to get yourself that last little step of the way."

"I need an answer, Peter."

"Come now, Derek, you don't really expect it'll be so easy to be rid of me, do you?"

In a strange, spreading awareness, beginning at the dig of his own nails into the flesh of his palms, the further thought occurs to Stiles that – mad though Peter may be – that he's not so mad as to have lost the knack for deliberate cruelty. And much like his last such observation, once he's thought it, all he can think is how breathtakingly that understates the reality of what he's watching Peter _do_.

"We're not..." Derek starts, and stops again. "We're trying to _help_ you. To set you free."

"How noble," Peter muses. "Though – hypothetically speaking, of course – it might be nobler still if you'd only first thought to _ask_ if being 'freed' was what I desired."

"Peter," says Derek, sounding horribly tired, "no-one takes the bodies you've been using as anything but a last resort."

"Don't they? But how many of our kind have ever had the _opportunity_? Oh, I'm sure this half-living existence would begin to weigh on one eventually, but thus far I feel I've hardly begun to explore the possibilities it grants me."

"What you've donewith those bodies breaks every tenet you ever taught us!" Derek snaps, patience finally wearing thin. " _Never_ kill those who'll be missed! _Never_ reveal your own to humans – let _alone_ to hunters! Two of the _first three rules_ central to _everything_ our survival depends on-"

"Are they?" Peter wonders, tapping his fingers thoughtfully against his chin. "What _was_ the third again? Do remind me – did those two come before or after the one about never going back for seconds?" The look he directs to Stiles is hardly a flicker of a glance, but it's enough.

_Oh Jesus_ , thinks Stiles. _He_ knows _._

If Derek spots Peter's implication – and it's hard to imagine he could've missed it – he refuses to be diverted. "If this is your way of punishing me... maybe that's your right. But this doesn't end with us. Two of my own charges are imprisoned thanks to your interference. They're hardly more than children, Peter."

Peter laughs, short and startled. "And how many guard them now? Ten men? Twenty? So many more than you could _possibly_ hope to overcome? Do you know how many hunters it took to kill Laura? How many I tore limb from limb on waking? Is it so much to ask you kill even _one – single – hunter_ now,in the name of _family_?"

Derek seems to hunch in on himself. "It never ends with one."

"But it would make such a good _start_!" Peter exclaims with eerie delight. "Tell me, did Laura ever tell you how I came to make the mistake of breaking my own geas?"

Derek hesitates, shoots half a look at Stiles. Stiles does his best to communicate with only his eyes that he should follow this line up; it's at least as close to the what they need out of this as anything they've got out of Peter yet, but Derek's already looking away again.

"Only that you made it with a hunter," he tells Peter, uncertain.

"Well?" asks Peter. "Didn't you ever wonder what cause a demon and a hunter could possibly have to bring them together?"

Derek frowns, as if hunting for the trick in the question. "You can make a deal without mutual interests."

"Oh, your survival for mine, your life for your silence, but what self-respecting son of Lilith would see himself trapped by an exchange so simple? Please, Derek, tell me you think more of your old friend than that."

Derek hesitates, thinking. "So it was more than life or secrecy?"

"Don't make the mistake of assuming the hunters have ever been wholly blind to our existence," says Peter. "You can't ever wipe out our kind, we spring up like weeds in the garden of man – they know to expect it. Even a hunter can occasionally manage to recognise that it might be better to leave an experienced elder or two on hand to seek out the young among us, when the alternative leaves them adrift..."

"...to find their own masters," Derek finishes, beginning to understand.

"Think, Derek! What's the one thing both incubus and hunter would prevent at all costs? What one act is so forbidden that even knowledge of how it could be achieved is a death sentence by their own code?" This time, Peter leaves no more than the briefest meaningful pause before supplying the answer to his own question: "The means by which to enthral our kind."

"How does that lead to you dealing with hunters?" Derek asks, his frown deepening.

Peter waves a hand in lofty fashion. "Oh, I'm sure you can imagine – one of _them_ finds word of some high scholar of too much renown to be dispatched with ease by a hunter's hands, who's taken to making worrying requests of acquisition from his servants; one of _us_ arranges for that scholar to be found stiff and cold in a locked room, without any explanation but that of some sudden, horrible malady – mercifully brief. Or perhaps one of _us_ finds news that an old text of suspicious character has fallen into the hands a village hedge-witch with delusions of grandeur, but the unfortunate good sense to lay a ring of mountain ash around her dwelling each night. Surely you see how we might help one another."

"Hunters would agree to that?" asks Derek, skeptical.

"My dear Derek, generations of hunters have agreed to the same. The deal _I_ struck was no more than the latest incarnation of an old tradition." Peter looks upward, his face turning wistful. "How easy it is to look back on that day and wish I'd only thought to word our agreement differently."

"What happened?"

"Oh, my hunter dispatched the witch I directed him to, and relieved her of that troublesome text that had so concerned us both. Unfortunately, it shortly proved that he intended to _keep_ the text in question for his own misuse. There was some elaborate excuse about protective seals preventing the deed, somehow voiding his obligation to give me the damned book the way he ought, all through some sort of dubious reasoning I won't bore you with. A thoroughly transparent excuse – not that he cared or even hid his satisfaction that he'd found himself an out from our bargain." This whole explanation emerges in casual and airy fashion. Peter shrugs. "Naturally, that left me little option but to kill him. Even if it did mean exceeding the terms of our deal to do so."

"So the deal you broke _was_ your safety for his?" The interjection comes from Stiles, to the general surprise of everyone in the room, including himself.

Peter twitches and throws a sour look at the source of the interruption. "In a manner or speaking, I suppose," he allows.

"Laura said you did it to protect the rest of us," says Derek.

"Did I?" replies Peter, forgetting Stiles again as quickly as he'd noticed him. "It becomes so hard to recall those sorts of details... though I never will forget the surprise in his eyes as I slit his throat." That wistfulness returning to his features, he continues, "You know, even now, I think back on that moment, and I can almost feel it was all worth it."

"What happened then?" asks Stiles, eager to push this back onto some sort of useful track. "You went back to the witch?"

"Oh no, she was quite dead and would hardly have been trustworthy in any case," says Peter. "Besides, _I_ was in no state to do anything. No, Laura found us _another_ witch and convinced her my life was worth saving."

"My mother," says Lydia.

"The one truly inspired facet of her solution was to find the means to trap me in a dreamless sleep, to last the span of my sentence of pain," Peter explains. "Sealing my soul beyond the confines of my own body was little more than insurance, a measure to entomb me in this world even if I woke early and sought to leave it."

"And to give her time to find a spell to free you of your pain," adds Lydia.

Peter glares at her sideways. Stiles mentally awards Team Derek another point and then wonders exactly when conversing with the demonic dead became such a petty exercise.

"And?" says Derek. "Where did she seal it, Peter?"

"And here we return to the question at the heart of it all." Peter smiles as though Lydia's correction had never happened at all. "It must be something within the bounds of this Tower, or I wouldn't have been drawn back here, but what? So _many_ possibilities."

"Peter," Derek warns, again.

"Naturally it would _have_ to be something whose safety she could guarantee for seven years and more."

"What _is it_ , Peter?"

"Hm..." Peter muses, with an exaggerated air of thought. "You know, I think and think, but it just won't come back to me. Perhaps another nice stroll in the woods would be in order, to clear my mind. You can't imagine how those wolf bodies I've favoured of late come alive under the skin once you've fed them a human soul or two – it's quite the most remarkable feeling."

"We don't have time for this, Peter."

" _I_ have time. From where I stand, I have just about all the time in the world. But you know what my one true regret is, at this moment? "

" _Enlighten_ me," Derek spits.

"That in all my time beyond the grave – all those wolf bodies used and discarded – I've not had chance to kill a single hunter. Why, I've hardly even managed to get their attention."

A short, dangerous silence follows Peter's proclamation. The intent is not exactly subtle.

"What exactly do you expect me to do, Peter?" says Derek. "Slaughter a few hunters and call you back again?"

"Come now, Derek, that's hardly your only option," says Peter. "You could always burn the Tower to the ground and everything within it. You could hardly miss whatever I'm bound to then. Or if all else fails, you could always _guess_." With an evil gleam in his eye, Peter turns to Lydia. "You know, the sorcerers of old faced this very conundrum when they brokered deals with demons, binding their souls to render their bodies well-nigh invulnerable. Naturally, they wanted something that would be well-cared for whatever hands it fell into – perhaps that's the very reason so much heirloom jewellery turns out to be haunted! Some of those sorcerers had a better solution, though, for deals on which there could be absolutely no room for doubt – do you know what it was? They would bind that demon's soul into the body of their own firstborn son or their dearest daughter – thus ensuring only with the sacrifice of their own child could that demon ever again come to harm."

"You're saying your soul is in _Lydia_?" Stiles exclaims.

"Oh, I'm not saying anything of the sort, but it would explain so much, don't you think? Something to consider, if burning the Tower to the ground doesn't bear fruit."

"You think this is a matter for _riddles_?" Derek growls.

"I'm sorry," says Peter, "were you under some sort of impression I was going to go quietly? Well, allow-"

Whatever Peter might have allowed goes unrevealed. He vanishes from the circle, mid-sentence, in a cloud of silvery dust which spreads across the circle as if thrown.

Stiles and Derek both turn to Lydia, now dusting off her hands.

"I don't know about you two, but I'd had about enough of that conversation," she declares, leaving Stiles in silent debate over whether he wants to chide her for impulsiveness or cheer.

Derek sighs quietly. "He wasn't going to tell us what we needed to know anyway. This was a waste of time. We're no closer to an answer than we were when we started."

"He didn't mean that part about it being Lydia, did he?" Stiles asks, if only because he desperately needs someone to convince him otherwise. The idea makes a compelling sort of sense no matter which way he looks at it.

"He wouldn't have raised the idea at all if there was any truth to it," says Derek, bitterly.

"Even if it _was_ true, we could have easily transferred his soul from me into something else we could safely destroy," says Lydia, who is clearly more than a little rattled by the events of the summoning no matter how well she's hiding it. "Unfortunately for that particular theory, we'd have noticed the effects of a pre-existing demon soul in my own body longbefore you and I finished our working theory of will-binding. Which makes _me_ about the one option we can safely rule out."

Derek huffs and begins to pace, impatient.

"Isn't there a spell we could do to find it?" asks Stiles.

"I know one to tell us whether a _particular_ item has a soul bound to it," says Lydia, "but we'd need to recast it for every piece we wanted to check."

"Burning this place to the ground is starting to sound like a good plan," Derek grumbles.

"It mightif my mother wasn't bound to have _fireproofed_ whatever object she used!" Lydia argues.

"Well that makes it easy," replies Derek, sarcastically. "We only have to set the fire, then smash the one thing that doesn't catch!"

"Surely we can at least start by assuming it's got to be among my mother's personal effects," says Lydia.

"Wait a second," says Stiles.

Derek and Lydia turn to look at him in tandem. Stiles takes a breath.

"Your book on demonology – the one Kate found up here – just how long had your mother owned it?"

Lydia blinks at him. "Is this leading somewhere?"

"You told me once there was some reason that book was 'never to be removed from the Tower'. But you didn't know why," says Stiles, thinking aloud.

"Are you saying Peter's soul is in one of Lydia's books?" asks Derek, less than convinced.

"I think that book might be the same one out of Peter's story," says Stiles. "You just _did_ one of its spells with only your other books – half the magic in it was repeated somewhere in your ancestors' old notes. Why would they need that if they'd had the book the whole time? What if your mother only got hold of it a couple of years before she had to leave?"

"You think she got that book from Laura?" Lydia supplies.

"Think about it: it has a _whole chapter_ on true will-binding! Peter was so concerned about that knowledge falling into the wrong hands he was willing to get the hunters involved! How many books like that could there be in the whole country? Laura would've found it with Peter after he killed that hunter. Any witch who could find a way to save him was probably going to need the sort of information only a book like that could give her, and Peter spent years making sure _no-one had that knowledge_." Stiles breathes out and in again. "I think the book was the price Laura payed your mother for what she did for Peter. It would have become her most prized and secret possession – the _perfect_ place to seal a demon soul! As long as his soul was stored there – as long as it couldn't leave the Tower – that was _her_ guarantee that Laura couldn't have it stolen or destroyed. Of _course_ they sealed the section on will-binding, That must've been part of the deal!"

Lydia and Derek stare at him. Then they stare at each other.

"That sounds like exactly the sort of deal Laura might have made," Derek allows.

Lydia purses her lips. "There's a certain elegance to the theory, it's hard to deny."

"It's got to be!" crows Stiles, triumphant. Now all they have to do is grab the book from wherever Kate moved it, and destroy it, and Peter will...

"We're not destroying my book," says Lydia.

"Lydia, I know it means a lot to you, but this is _not_ the time to get sentimental," Stiles argues.

"We're not destroying my book, because we _already know_ there's a protection charm preventing that. If Peter's to be believed, it's been under a protection spell since before my mother ever laid hands on it – and if it wasn't, she'd have worked one herself. You don't risksomething that important."

"So... we have to unseal his soul without damaging the book?"

"Tricky. The easier option would be to transfer it into something else." Lydia picks up a large, earthenware jar, stoppered at the top. Stiles recognises it; up until now, she's been using it to store her personal hoard of mountain ash. "Something _breakable_."

"Wouldn't there be protection against that too?"

"His soul was always meant to be returned to his body once his sentence was up," says Lydia, reasonably. "We have part of his last physical body here. We have a member of his own kin to donate a few drops of authentic demon blood. I've done this _exact_ spell before. I could do this in my sleep."

"How long will it take?" asks Derek.

"I'll need to prepare the vessel first. Inanimate objects won't take a binding as readily as a living body. We'll need the book before we can do the transfer. I can draw the circle and finish this downstairs. It's not nearly as complicated as the one for the summoning."

"Alright," says Derek. "Do what you have to."

Lydia nods back, sets the jar on the floor and begins paging through her notes.

For a minute, Stiles and Derek stand and watch her work. The buzz from his great moment of genius only a minute before is starting to fade, rendering the rest of the process uncomfortably anti-climactic.

"So," says Stiles, "did we... ever sort out exactly how we're going to get past those hunters downstairs?"

"Boyd will be singing them to sleep as we speak," Derek replies.

Stiles blinks at him. "He can do that?"

"Those hunters have been on guard without distraction for over an hour. Boyd could probably put them out with five minutes of humming. We can pat them down for the keys while they're out."

"Oh," says Stiles. Sounds like they _do_ have a plan.

For several seconds, there's no sound but that of Lydia's chalk against the floor.

"Ask," says Derek.

"Huh?"

"If you have other questions, now _is_ the time."

"What makes you think I have other questions?" says Stiles, stalling. "You can't read that stuff off me anymore, right?"

Derek looks at him sideways and raises his eyebrows.

Stiles swallows. "So... you're not tempted to maybe... follow some of Peter's advice while they're defenceless?"

Derek blinks at him, as if this isn't actually the question he was expecting, which only makes Stiles feel all the more of a coward for leading with the one he felt less nervous about asking.

"I couldn't hurt them if I wanted to," Derek replies, sounding tired. "I'm still under your geas against harming anyone within the walls of your tower, remember?"

"Oh, right." Stiles had actually forgotten about that little clause. It seems like something from a lifetime ago. He supposes he could offer to free Derek from it now, but changes like that wouldn't take effect until dawn anyway. Not that he especially wants the hunters' blood on his hands. "Sorry."

"Besides," says Derek, "any surviving hunters would take three escaped prisoners and two dead guards as a declaration of war. Three escaped prisoners and two _sleeping_ guards is just an embarrassment. We don't need to give them more reason to come after us."

Stiles nods. Swallows again, and finally opens his mouth to ask, "After all that, you and Lydia and the others – you're all just going to... go?"

Derek is quiet a moment before he replies. "We don't have another option."

Stiles nods absently, and tells himself he was ready for that answer. That he's known it was going to come to this since... since Derek said so, back out in the woods? Since Derek revealed himself to the hunters, swooping out of the sky to snatch Lydia out of harm's way? Since they caught Erica and Isaac fighting off the volkodlak? Up until the fair, he'd maybe sort of assumed it was always going to end this way eventually, except...

...except for some reason, Derek is still talking.

"I know you've given me your answer before," he says, eyes fixed on a far wall, "but the offer is still open. You can come with us, if you want to."

Stiles gapes at him stupidly. Tries to convince himself of what he just heard with little success. "But Peter said-"

"Forget Peter," says Derek, with some vehemence. "He doesn't have much moral high ground to lecture me from."

"Do you _want_ me to?" Stiles asks, stupidly.

Derek looks at him, vulnerability writ large across his every feature, and Stiles thinks, _oh_.

Derek's asked him this before, Stiles thinks, dizzily. He said no then. That should still be his answer now, right? "What about Scott?"

Derek shakes his head. "As long as the hunters think he'll cooperate, Scott's safer here."

"What about Jackson?" asks Lydia, as if she can't even tell they're in the middle of having a moment over here.

"He'll more than likely be hung as your accomplice if he stays," says Derek. "If he wants to join us, he may."

The thought of leaving Scott to deal with the hunters alone leaves Stiles cold. Of his dad coming home to find him gone. Having Jackson along doesn't exactly sweeten the deal. But the idea of staying – virtually the last ordinary human servant left in the Tower now – with Lydia gone, with the hunters lording over everyone left, holds no attraction. Stiles doesn't think he _could_.

Ultimately though, maybe he's only than pretending any of that really matters when Derek wants him to come away.

It doesn't mean a thing that he's heard this offer before. Everything has changed since then.

"I'll go with you," he tells Derek and knows there's no other choice he ever could have made. It feels like a choice he'd made hours ago, if not long before.

"Stiles," Derek calls his name softly. Stiles blinks up at him at Derek raises a hand to lightly cup his face. Skin to skin, so Derek can feel his answer and know he means it.

"Thank you," Derek breathes.

Stiles tries to find the words to tell him he's not just doing this for Derek, it's that he can't bear the thought of staying... does that really matter though? Should they kiss? It seems like the kind of moment that calls for a kiss, and Stiles does kind of want to. Only in a minute, they're going to have to go downstairs and bust Derek's friends out of the dungeons, finish banishing Peter, then probably steal some horses and run as far and as fast away from here as they can. Maybe kissing Derek should wait.

"Finished," declares Lydia, pulling Stiles and Derek abruptly out of their reverie. Stiles comes back to the present to find Lydia is brandishing a bag in his direction. The jar, still sitting on the floor, now sports a complex sigil carved into its lid. "Take this down for me," instructs Lydia, meaning the bag. "I'll need what's in it downstairs to finish the circle."

The bag is heavier than it looks, which presumably means Lydia's remaining books are in there too. "What are you going to be doing?"

"Carrying the jar and finding Jackson," says Lydia. "You and Derek go free some prisoners and find my book. It's probably locked in their quarters. The guards should have a key for that too."

Stiles makes a studied attempt to focus on taking the stairs between them and the dungeon as quietly as possible. It isn't easy; his mind is buzzing with the enormity of everything he just agreed to. It feels inevitable. It feels like a decision that should've been much harder. He can't begin to trace how everything got to this point without losing the thread in an infinite obstacle course of snags, each one pointing the blame in different directions. He can hardly stand the idea of leaving Scott, but there's nothing left he can do for Scott anymore that Allison won't be placed to do better. He's already planning how to get a letter back to his dad to let him know he's alright. Is there anything he needs to grab from his room before he leaves? It's probably not a good idea to leave his notes on the volkodlak where the hunters could find them.

The next step down fails to materialise where Stiles' outstretched foot was expecting it to be. He clips it with his heel and topples forward.

Derek, silent as a cat in the gloom two paces ahead, catches him almost before Stiles has realised he's falling. "Careful," Derek hisses, though as a warning it comes a little late.

"Sorry," Stiles breathes back, mostly on automatic. Being unable to see only leaves him that much more aware of how close they're standing. Derek's voice is actually coming from behind Stiles' head. His hands seem to have found Derek's shoulders, somewhere mid-flail. It's almost an embrace.

If only the context were a little less mortifying. "Um, can we maybe pretend this _isn't_ the second time tonight I've nearly fallen on you?"

Derek chuckles. "What do I see in you," he murmurs, though it comes out sounding fond. Stiles can only imagine whether his eyesight is good enough to make out the colour of Stiles' cheeks in this light.

The longer they stand here, the more Stiles is aware of Derek's presence in his space. After everything that's happened today, that this kind of casual intimacy is possible for them at all feels enormous, for all that it should be the most mundane thing in the world. Halfway down a stairwell is probably not the best place he could have chosen for this particular moment of clarity. He's starting to think not giving himself a minute to sit down and process upstairs might have been a bit of an oversight. Not that a minute could have realistically been long enough.

Derek pushes him gently, if stiffly, back onto his own feet. "Nerves won't help anyone's balance," he allows. It sounds like consolation. There's no way he's unaware what Stiles was thinking.

"We can't all be supernatural acrobats," Stiles mutters. Though he learned to navigate the Tower in the dark almost as soon as he'd learned to walk, in the wake of the last few moments he finds himself quite disoriented. "What floor is this?"

"We're just above ground," Derek tells him. "The guards should-"

Stiles will never be entirely sure whether Derek stops a moment before or a moment after the volkodlak's howl comes echoing up from below. Magnified by the enclosed space, the source sounds dangerously close.

"No," Stiles breathes. "No, no, no, no, _he can't be here now!_ "

Derek doesn't tell Stiles to wait there or stay where it's safe, just turns and sprints toward the sound. Stiles follows – much as he would have regardless of what Derek might have told him to do – almost tripping over his own feet again more than once on his way down.

He catches up with Derek at the foot of the stairs to the dungeon. The same hunter Stiles had spoken to earlier lies sprawled across the doorway, his skin leached of colour and his neck twisted to an unnatural angle. It might be nice to believe that was what killed him, but the man's face suggests his death wasn't nearly so quick. His companion lies half on his side, folded at the waist towards the wall, his face obscured, though the skin on the back of the neck matches the same sickly hue.

Inside the dungeons, a third body – one with unruly hair, dressed in the skins and leather favoured by the wild pack – stands staring into Erica's cell. Erica herself is pressed against the far wall, as far from the intruder as her prison will allow. Peter takes his time turning around.

There's a warmth to the complexion of his latest body quite at odds with the scent of decay haunting the corridor in his wake. He has, perhaps, managed to drain his latest victims of pigment as well as life. In the gloom of the dungeon his eyes shine almost bright enough to blind. There's little enough of Peter in the creature's features, and Stiles would tend to doubt Peter would ever in life have so openly savoured the flex of his own fingers – joints that must respond with unaccustomed ease in the wake of his last meal. His grin too is different on this face, but that much in its own way is all him.

That two dead hunters would be enough to satisfy him is so laughable as to be barely worth the time it takes to form the thought. Peter is not going to let them get to the book without a fight. Maybe, if they hadn't known where to find it, they could have followed him to it.

Now that Stiles knows how much Peter loves the sound of his own voice, his silence in this body is unsettling. Though Stiles has heard the volkodlak howl or snarl more than he cares to remember, maybe speaking is harder in a body that has lost the habit of breathing of its own accord. What Peter does instead is to make a rough sound that might, in another life, have been laughter. His eyes flick briefly over Derek's shoulder, meeting Stiles' own with a look of intent that could scarcely be more clear had Peter mimed the slitting of a throat. Derek snarls and rushes at him with his claws bared.

It occurs to Stiles that he's never seen Derek fight before. He can only hope he's good at it.

The further thought occurs that if Peter does manage to get past Derek, even for a matter of seconds, Stiles is utterly defenceless standing where he is.

Crouched around the doorway, Stiles hunts madly through Lydia's bag, trying to find the mountain ash by touch without having to take his eyes off the fight. He's sure ( _almost_ sure) there's some in there, but locating it blind in a bag he didn't pack himself is all but impossible, and besides... oh god, if Peter's in herehe's already made it through the ash line outside the Tower, and Stiles renewed that only last week! How is that possible? Does it have something to do with how they summoned his soul from inside the ring? Did that negate the defence somehow? It never occurred to them to do a proper banishing afterwards. Stiles isn't even certain how to do a proper banishing. He's all but making things up at this point.

Jesus, why is he scrounging through this bag like the ash could turn up loose at the bottom? He _saw_ Lydia empty the last of her ash out of the jar only minutes ago, she transferred it into...

Stiles' fingers close around a small drawstring bag, its contents loose like sand beneath the fabric. Finally. He draws it out, then hesitates.

What good is a handful of ash even going to _be_ if all he can do with it is trap himself in a tiny circle while Derek and Peter go on tearing at each other's throats? The only way to win here is to disable Peter somehow, and Stiles doesn't even know whether Derek physically _can_ injure his body so much now – whether his old promise _not to harm anyone within the boundary of the circle, whether they live there or no_ applies to the living dead. But if they can draw Peter into some sort of trap – bait him into an incomplete circle, or draw one to cover a doorway, trapping Peter on the inside – that might just work. The dungeon would be perfect if only it wouldn't mean trapping Derek and the others in there with him. There has to be a way to separate them...

Looking for Derek and Peter means discovering that the fight has moved further into the dungeons, just out of sight. What Stiles eyes fall on instead is an empty cell – the one and only the hunters hadn't used. The door is open. If it's built like the others though, the door should lock automatically when shut.

Ash might not be the only way to catch a zombie-wolf.

A plan that is scarcely more than an impulse sends Stiles darting into the dungeons, setting his sights on the ongoing struggle just in time to witness Derek slashing Peter's body across the throat. The body staggers backward; for a moment Peter and Derek seem equally surprised by the spectacle of dark blood spilling thickly from his neck. Curiously, Peter runs his fingers beneath the wound and holds them up to his face.

The wound beneath is _healing_.

The realisation that Peter is scarcely injured reaches Derek a fraction of a second before the blow does – a vicious right hook that bounces his head off the wall with a sickening crack. Derek twitches, stunned but conscious, claws scrabbling for purchase on the wall, but Peter has already moved – his gaze finds Stiles with terrible ease.

The next thing Stiles knows is that Peter is coming for him, and whatever half-hearted plan he might have been forming about baiting Peter into the empty cell proves itself painfully short of ripe. There's no plausible sequence that starts with Peter following him in and ends with himself getting out. The possibility of jumping into the cell himself and slamming the door shut behind him becomes briefly, horribly attractive.

Then Peter's body stops short, almost tripping forward when his back foot catches on something out of sight. With a hand snaked between the bars of her cell, Erica has him by the ankle. Peter howls and claws at her face, but the bars make an effective obstruction, limiting his range. Furious, he slashes at the wrist holding his ankle, but Erica only digs her own claws deep into his flesh and hangs on.

He's completely and conveniently off-balance when Derek comes up behind him, grabs him by the strongest looking part of the clothing on his back, steps past and swings Peter through a stumbling arc that ends on the far side of the doorway to the open cell. Stiles slams the door behind him. Never has the sound a lock clicking into place been so musical to his ears.

It's all over well before Peter has his equilibrium back – let alone proper use of his shredded ankle. He doesn't wait to see how much it will heal though, just throws himself against the door with enough force to interrupt all Stiles' internal celebrations and send him skipping back out of arm's reach of the bars. Metal creaks under the assault; for one frantic moment, the possibility that the hunters had left that cell empty because the lock wasn't reliable hovers over the proceedings with a shadow that sucks the air out of Stiles' lungs. But once a second assault has landed on the door without shifting it – this one hard enough to scrape welts out of Peter's borrowed skin against the hard edge of rust on the bars – Stiles breathes out again. Peter howls in frustration, and seems to give in.

Derek probes the side of his head with his fingers and winces, eyeing Peter with distaste. "You just _had_ to have the last word."

"Derek, are you alright?" calls Isaac. "What he did to those hunters – I could've lived without having to watch that."

"I'll be fine," Derek bites out. Looking to Erica, he gives an approving nod. Well-accustomed to Derek's rather stiff approach to gratitude, Erica preens, rightfully pleased with herself.

Stiles eyes Peter and wonders if finding the excuse to poke him a few times with something sharp is going to be out of the question. What little sympathy he'd ever managed to summon for Peter's situation has largely evaporated in the wake of their last two encounters, in the flesh and out of it.

"What about him?" asks Boyd, tilting his head toward the newly-occupied cell. "Seems like a bit of a temporary solution."

Maybe Stiles isn't the only one worried about the state of the lock on that door.

"Better to have him where we can see him," says Derek, glaring at Peter with a look of open hatred – one that would suggest he too is mostly over his own misplaced guilt on Peter's account. "This could even be useful. We can finish the ritual here. Watch and see if it works."

Peter snarls and lunges for the bars. Not having Derek's mettle, Stiles jumps backward. Rattled, he tugs Derek away from his staring match. "Maybe don't aggravate the crazy demon," he suggests, voice pitched in a low hiss.

Peter makes a hissing noise of his own, another strange imitation of laughter. Stiles thanks his lucky stars Peter can't actually talk like this.

"What in the name of hell...?" calls Jackson's voice, coming from the doorway.

Stiles whirls to find both him and Lydia surveying the scene of the dungeons – bodies in the doorway, imprisoned volkodlak and all. The scene speaks for itself, mostly.

* * *

In a more ordered universe, Derek's struggle against a surprise enemy ambush would have been some sort of climax. In the one Stiles is stuck with, there's an unfinished surfeit of inglorious busywork left before they can make their escape. Lydia takes the news that they're going to have to finish the ritual with Peter's leering werewolf-skin looking over their shoulders with relatively good grace, all considered.

Jackson takes in his first sight of Derek in all his demonic glory with slightly less dignity. Stiles can practically see the moment he decides the sight is no more terrifying than Scott in werewolf form, then abjectly fails to make himself believe it. It would be nice to know exactly what Lydia told him about the situation.

Stiles coughs politely. "Uh, Jackson, this is Derek. Derek – Jackson."

"I gather you've already met Peter," says Derek, looking over his shoulder at the nearest cell.

If by 'met' you include 'once had your dislocated your shoulder by', this is perhaps technically true. It feels like an age ago. Jackson, never best known for schooling his reactions, rubs his arm as he stares into Peter's cell – a habit he'd picked up and lost months ago as the injury healed.

"First things first," says Lydia, already laying out her chalk. "I have a circle to draw. Someone needs to relieve those hunters of their keys."

If picking the pockets of the two sleeping guards in the original plan was never a job Stiles would have been first in line for, picking the pockets of two fresh corpses is infinitely worse. He locks eyes with Jackson, who unfortunately seems to have reached much the same conclusion. Stiles attempts to communicate that this is definitely not his job.

Several seconds of increasingly emphatic eyebrowing later, Derek rolls his eyes, and stalks over to the bodies of the guards himself. A minute of searching produces a single brass key.

"That's the key to the hunters' quarters," Lydia tells him.

"What about the keys to our cells?" asks Isaac.

Derek shakes his head.

"They may have thought leaving the key to a succubus' cell on the man guarding her was asking for trouble," says Lydia.

There's a sense to this that's hard to deny. "Maybe they left them in their quarters?" Stiles suggests.

"It's possible," Lydia agrees. "Jackson, you take the key, go see if you can find the others. Don't forget to find my book. Stiles, help me with this circle."

Jackson takes the order without complaint, though as he passes Stiles, he mutters, "Not really a witch, huh?"

Awareness that Jackson is never going to let him live that one down settles on Stiles uncomfortably. As if having agreed to run away with the guy – if only by proxy – wasn't bad enough. "She's still not a bad witch?"

The look Jackson gives him before going on his way is really no more than what that sorry excuse for a comeback deserved. As if Lydia would ever stoop to being _bad_ at anything she does.

For several minutes, there's little sound but that of chalk and Lydia's geometric instruments scraping across the stones floor.

"What if he can't find the keys?" Derek asks, while Stiles and Lydia busy themselves with the circle. "They may not be in the Tower at all if the hunting party took them."

Stiles and Lydia briefly lock eyes across the circle. Another possibility they haven't planned for.

"How are you at lock-picking?" Lydia asks.

"It's never been my first port of entrance," says Derek, darkly.

"See," says Stiles, shoving a compass back into Lydia's bag, "this is why no-one believes you when you tell them you don't spend your life lurking on window sills."

"Maybe we won't need to," Isaac puts in, kneeling to examine the door to his own cell. "The hinges on this thing have seen better days. If we took a hammer to them – or maybe if I push and you pull..."

The circle now all but done, Stiles sits back on his heels and looks over at where Derek and Isaac are now both intently studying the construction of the hinges. Isaac may be overly optimistic, but it's better than no back-up plan at all.

He's still on the tail end of that thought when Jackson reappears at the door, Lydia's missing magic book clutched to his chest.

"Well?" prompts Lydia. "Did you find the keys?"

"Um," says Jackson, which sounds discouragingly like a 'no'.

Stiles is still processing the fact that Jackson looks oddly spooked when Kate Argent steps around behind him in the doorway, a loaded crossbow pointed at his head.

It takes Kate all of a second to take in the state of the room – and for Stiles to realise that everything has gone or is about to go horribly wrong – before her gaze settles on Derek with predatory interest.

"Well fancy meeting you here," she says and raises her crossbow.

The bolt hits Derek in the gut.

**Notes for the Chapter:**

> Hoping to be able to pull off a reasonably regular update schedule between here and the end - more info [over on my tumblr](http://rallamajoop.tumblr.com/tagged/dangerous%20things). 
> 
> Some further notes/ramblings about where this whole idea came from can be found [here](http://rallamajoop.tumblr.com/post/48849555925/dangerous-things)


	17. Chapter 17

**Notes for the Chapter:**

>  **Warnings/Content notes:** Since it's probably been a while since most folks read the warning notes attached to chapter one, I'm just going to take a moment here to remind people they're there, as they're about to become relevant again. Details are a bit spoilery, but if you'd be more comfortable going in with more idea what you're in for, highlight the below to read.
> 
>  Contains sexual assault/attempted rape (female on male), and reference to an instance of actual rape (also female on male) which occurred in the past.

The dungeon around Stiles erupts in the time it takes him to get to Derek's side. Derek roars in pain and collapses to his knees. Someone – probably Erica or Isaac – calls Derek's name. Jackson wheels on Kate, only to meet the butt of her crossbow coming the other way. The blow hits him on the side of his head and he goes down like a heap of rags. Someone – presumably Lydia – calls Jackson'sname. None of this, nor whatever self-congratulatory nonsense Kate is spouting as Derek crumples, makes much impression on Stiles in the moment. This time, he has his hands on Derek before he's entirely remembered why it would be a good idea. That he's instinctively put himself between Derek and the danger doesn't quite become apparent until Kate's voice starts coming from behind him.

By then, it's all over.

Derek's breath is coming in short pants, gaze fixed on the scene over Stiles' shoulder. Stiles cranes his head around to see Kate ordering Lydia into Boyd's cell, locking the door behind them. Her crossbow sits balanced on her arm, already reloaded.

"And here I almost thought doubling back on your own tracks might be a little _too_ obvious a ploy." Kate sighs lightly, laughter on her lips. "Suppose you never can beat the classics."

She retrieves Lydia's book from Jackson's slack-fingered grasp without resistance. The circle on the floor only gets her attention for as long as it takes her to scuff a few lines with her toes. The jar with the sigil newly-carved into its lid she kicks over, hard enough that it cracks against the floor. "I'd ask what you were hoping to do down here, but it's not as though I'd trust the answer, and if I'm really honest, not sure just how much I care. Maybe I'll see if this can tell me later," she adds, hefting the book under her arm to free her hand to fish through one of her pockets. "Now, just to head off any smart ideas anyone might be having..." She brandishes the key ring briefly for all to see, then tosses it neatly through an upper grating and out onto the courtyard outside. The keys land with a faint jangle, well out of arm's reach.

Something about the gesture only adds to Stiles' considerable unease. What is she doing? That can't be standard procedure.

Kate, meanwhile, stops by Peter's cell next, studying him with obvious contempt. "Now don't tell me – _this_ is your volkodlak!" She grins at the greater room as though she's said something terribly funny. "Not a bad way to cover for the activities of... what is it, three, four incubi? But why am I getting this _little inkling_ he's not been behaving himself?" Peter's low growl inspires no worse than giggles from his new jailor. "Isn't that always the problem – they're only ever worth the trouble as long as they know who's in charge."

"You think we..." By the time Stiles has finished that thought, saying it out loud feels superfluous, a waste of breath. Kate's whole twisted theory is there for him to unpack in a single moment of insight. Allison was right: there was never any part of this the hunters couldn't find some way to pin on Lydia.

Kate raises an eyebrow; her eyes alight on Stiles with a twinkle of great amusement. She strides over to him – practically prancing on her tip-toes.

" _Actually_ ," says Kate, as if imparting some great secret, "I think _she's_ behind it all. No offence, but I don't really think raising an army of demon-slaves is particularly your style, even if you have been... enjoying some of the benefits," this last comes with a glance at Derek, who glares daggers back. "Oh yes, I _remember_ you. You aren't going to slip away from mea third time – we have unfinished business." Returning her attention to Stiles, she goes on, " _You_ , Stiles – you I could be convinced have been merely... lead astray. But you have gone and got yourself caught in a fairly compromising position, and we can't just let you off the hook for that." Kate jerks her crossbow significantly. "Both of you – to the far wall. Move."

Teeth gritted, leaning most of his weight on Stiles, Derek barely levers himself to his feet. They progress through the dungeons one step at a time. There's no free cell left at the far end of the dungeon, but there's little mystery why Kate wants them back there. What's at the back is for those prisoners who didn't confess on their first opportunity, who don't get the luxury of bars between themselves and the guards.

"Put him against the wall, there," Kate instructs, shadowing them step for step. "Then the chains. Put his hands in the leg-irons, behind him. He can stay seated."

Numbly holding onto the fact that at least if Kate wants Derek chained up, she can't mean to kill him right away, Stiles obeys. As long as she'll at least let him keep touching Derek, that's something. Gingerly, Stiles reaches to pull the arrow out of Derek's midsection.

"Uh-uh," says Kate, stopping him. "No, I think we'll leave that there. Shame to waste such a good opportunity to see our new poison in action. Speaking of which," and she pulls the trigger on her crossbow. 

So close, the twang of the bow is startlingly loud. The bolt buries itself in Stiles' shoulder.

Strangely, Stiles is aware of Derek roaring and flinching away from him almost before he's aware of the pain, which explodes from his shoulder in a red haze. For the second time in no more than a handful of hours, Stiles is Laura, brought down beneath a hail of arrows. The pain is more than excruciating. He can't breathe.

Awareness that Derek is calling his name is the first thing that reaches past the fugue of agony. Stiles' first instinct is that he has to let Derek know that this isn't real – he's only experiencing someone else's pain. It'll pass as soon as the vision is over and he comes back to himself.

The vision of Kate tilting Derek's chin upwards with the blade of a dagger doesn't go away.

"Really?" Kate seems to be saying. She's looking Stiles' way. " _Him_? I thought you at least had _slightly_ better taste." She looks back to Derek. The dagger goes back into a sheath at her belt. Only Kate's empty fingers come back to ghost their way up Derek's bare chest, starting from the place where the arrow shaft still protrudes from his flesh, never quite making contact. "Or is this just that inconvenient _empathy_ ," Kate spits it like a dirty word, "your kind inflict on yourselves whenever you get your hands on one of us?"

Kate closes her hand around Derek's throat. Not tight enough to choke – though the implied threat could scarcely be clearer – but that's not the worst of it. The worst is the way Derek's laboured breathing eases, his eyelids drifting downwards briefly at the touch. The very same reaction to when Stiles had been touching him; only now he's feeling what Kate is feeling instead.

Even through the existing haze of pain, Stiles feels his stomach turn over, tasting bile in the back of his throat. He feels sick. Nothing about what he's watching has anything to do with mercy.

If Stiles notices Derek's reaction, Kate is hyper aware. "Oh, he _likes_ that," she croons, delighted. "Does that take some of the pain away?" Her gaze flickers down. Still holding Derek by the throat – tightly now, forcing his chin upwards – she cups his hip with her other hand and runs her fingertips over his stomach until she has the arrow shaft caged between her fingers, two above and two below, trailing through the dark line of blood trickling downward. Derek twitches at the pressure, stifling the edge of a groan. His eyes remain fixed on Kate's, unreadable.

"Potent stuff, that poison," Kate says. "Just a couple of drops, and it heightens sensation to extremes." She takes hold of the arrow and twists. Derek spasms, his whole torso flinching uselessly away, and groans in pain.

Kate laughs again, and Stiles sees red. Watching Derek writhe without himself tensing in sympathy is impossible, and tensing around the arrow head buried in his own muscle is an act he pays for. The miserable truth is he'd welcome all that pain and more, if only by doing so he could banish Kate Argent from the face of the earth. Stiles has never before realised he could hate anyone half so much as he hates her in that moment.

"What _I_ wonder though," says Kate, more casual than she has any right to be, "does it heighten any sensation, or is it just pain?"

That Kate's hand is leaving the arrow is a relief for all of the second it takes Stiles to realise where it's going next.

In demon form, Derek habitually wears no more than a loin cloth, if that – little more than a hanging flap of loose fabric, enough barely to redirect attention away from his nudity when he might want to use of his demonic visage to some other effect. Kate plucks the cloth unceremoniously out of the way. Exposed, Derek's cock hangs limply in the V of his thighs, and Kate leers at the sight, licking her teeth without the least suggestion of shame. One hand still braced on Derek's throat, she leans down as if for a better look. Dipped close enough that the bottom of her chin is hidden from Stiles' angle behind the nearer of Derek's legs, Kate opens her mouth and exhales, a gust of warm air directly onto the flaccid shape beneath.

Derek gasps, sharp and surprised. It's not the sound of someone in pain, not even a little. The reaction below is less subtle still – even from Stiles' vantage he can see Derek's cock beginning to stiffen. Kate lights up with delight. " _Any_ sensation it is!"

For a moment Stiles believes, stupidly, that he's witnessing the point beyond which this can't get any worse, and there's nothing comforting in the thought. With this, Derek's humiliation has to be complete. It's only when Kate lowers a hand between Derek's thighs and starts to play with him, watching Derek's face with gleeful fascination at his every stifled reaction, that it comes to Stiles that she's nowhere close to done.

The single word, " _Don't_ ," comes rasping out from between Stiles' lips. It's possibly the single weakest objection he's ever made in his life.

Kate looks at him as though she would a worm. She laughs. "What, you think he's _yours_?" she scoffs, yanking Derek's head back by the hair."As I see it he's _anyone's_ just now."

Derek hardly flinches at the casual manhandling. If Kate meant to underline his helplessness, nothing in his bearing contradicts her. His eyes, however, flicker briefly to Stiles and back again, and Kate doesn't miss it.

"What, does _he_ still mean something to you?" Kate huffs, bemused. "There really is no accounting for taste." Biting lightly at her lip, she glances at Stiles and back again. "He's not going to get off lightly, you know," she says, to Derek, "the punishment for aiding and abetting a demon _starts_ with execution. The only question of degree is a matter of slow or fast."

Derek is in no state to control his reactions, and Kate is watching for the moment he tenses at the threat. "Does that bother you? I _could_ be convinced to be lenient – say, if you were willing to cooperate with me on a few little things in exchange."

Derek looks at Stiles again. The glance lasts only a second and says more than Stiles can begin to unpack. "What do you want?" Derek asks, aloud.

"Right now," Kate makes a minor show of thoughtfulness, "you know, in theory I'm supposed to interrogate you, if I don't want you dead right away. So what's say you make me a promise you'll tell the truth, and I won't kill your boy. Sound fair?"

" _Derek_ ," Stiles rasps. _Don't deal with her_ , he begs, silently. Derek has to be able to hear it in his voice.

"Agreed," pronounces Derek, stiff but clear.

Kate beams. "Alright then, _Derek_ , if that's your name. First question: are you bound to that boy?"

"No," Derek replies. Stiles quietly thanks his lucky stars that's an answer Derek can give under the circumstances.

"Well that's something," says Kate. "What about the witch, Lydia? You bound to her? You know we _really_ don't look kindly on that sort of thing."

"No."

"To anyone?"

"No."

Kate raises her eyebrows. "But you have fucked at least one of them, right?"

Derek carefully does not look at anyone but Kate. "Yes."

"More than once? Actually, why don't I cut to the chase here. See, while I was waiting for the fun to start, I did a little reading up on just exactly how that whole forbidden bonding thing works." Kate taps Lydia's book, lying on the floor beside her, lest there be any doubt exactly what she means. "Maybe you can tell me whether I've got the whole picture. Is it really true that all it takes is a few rounds with the same human?"

Derek's eyes widen. Pain and nausea is making Stiles hazy, but Kate's words send a chill straight to his bones before he's even realised why.

"It's true," Derek intones.

"Huh. How many rounds would that be exactly?"

"I don't know."

"Come on, you can give me an estimate, surely."

"More than two," says Derek, slowly. "Less than twenty. It might depend on the people involved."

"One more question then," says Kate. "How many do you reckon it might take between me and you? That poison in your system would have to help. And we're already off to such a good start."

Derek stares at her in mute horror. Stiles thinks his heart has actually stopped.

"You can't!" he rasps, uselessly. From the direction of the cells, Erica's voice breathing the word 'No,' carries amid a horrified murmur, like a chorus line of spreading horror. Derek begins to thrash, trying against hope to throw Kate off him.

"Uh-uh-uh." Kate hardly has to brush the arrow shaft for Derek to hiss in pain. She watches him writhe with some interest for a handful of moments, then puts her hand back on his cock. Derek begins to pant. He doesn't try to throw her off again.

"Good boy," says Kate.

Stiles tries to stand. He tries to pull the arrow out of his shoulder. The world goes grey. Something like cobwebs seems to be creeping in around the edge of his vision. He isn't sure if he's seeing or hallucinating the image of Kate standing and taking off her belt

There has to be something he can do. He thinks about Scott telling him _if not you, then who?_ He thinks about having to watch while Kate rapes Derek until Derek stops protesting. He thinks about praying, though what comes out is barely a whisper that sounds a little like, "Scott, if you can hear me, you have to get here. Scott, god, _anyone_ , please."

He thinks, very seriously, about passing out.

Kate is starting to take off her pants. Stiles is a coward, and he looks away.

He doesn't hear anyone coming. He's mostly convinced his first blurry glimpse of Allison is a hallucination.

"Kate?" The uncertainty in Allison's voice has nothing to do with doubt about her aunt's identity. She holds an arrow notched in her bow, but in the doorway her draw falters, her aim falling to the floor. "What are you...?"

A normal person would probably be embarrassed to be caught in the position Kate is in. Then again, a normal person wouldn't be in the position Kate's in, so it's perhaps not a terribly relevant standard.

"Didn't we ever teach you to knock before entering?" Kate grins at a joke no-one else is likely to find amusing. "Good news – I caught our last demon! _And_ our witch, and all her accomplices."

"I can see that," says Allison. "Now explain the rest of what you're doing."

"Oh honey," says Kate. "I thought we'd had that talk."

"Is this a joke to you?"

"She's trying to," Stiles manages, "what _I_ did to Derek." He pants. Talking hurts. "She _knows_."

Allison's eyes widen. " _This_ is how you put an incubus in thrall?" Her bow isn't pointing at the floor anymore. It's pointed at Kate.

"Well, if I understand the theory." Even now, Kate's grin betrays maybe a little embarrassment, if that. "Come on, little niece, why so shocked? I thought we talked about how badly our profession needs some new ideas! It's hardly fair if _you_ get to be the only one with your own tame monster at your beck and call."

"'Taming' Scott didn't involve stabbing him and chaining him to a wall."

"Not even during full moons?"

"There is a _difference_." Allison's bowstring is now tight enough to creak. "Some taboos exist for a reason."

"Funny. You know, I could've sworn I heard your father say the exact same thing earlier today. I don't have to spell out the context, do-"

"Move _away_ ," Allison orders, "from the demon, Kate."

Kate raises her eyebrows. "Allison, come on. I know walking in on this has probably got to be a little confronting – you're a little on edge, that's understandable. I promise you we can talk this through as much as you like just as soon as I'm done making sure this one's nice and properly subdued. Now if you could just give me a _little_ privacy..."

"I think the talking needs to come first," says Allison. "This is your last warning. Step away."

"Sweetie," says Kate, "you and I both know you're not really going to kill me, so if you-"

Several things happen in quick succession. Allison's arrow hits Kate in the thigh. The scream of pain comes from both her and Derek simultaneously, though while Kate flinches, Derek throws her off his body with one powerful kick. Somewhere back along the line of cells, an eerie whistling whine of a noise begins. Kate lands on the floor several feet away in a defensive curl. She looks up at Allison in horrified betrayal.

Allison already has a second arrow notched into her bow. As Derek pants and gasps in renewed pain, Allison walks slowly across the room until she comes to Derek, so she can stand with her bare ankle pressed against his leg. Derek's breathing eases rapidly in response. She never takes her eyes off Kate. "Don't make me tell you again."

"Allison..." Kate whimpers.

"Let me tell you what we're going to do," says Allison. "We're going to wait here until my father gets back. I'm going to tell him exactly what I found you trying to do. If we're both very lucky, I might be able to convince him you don't deserve to die for it. And then..." Allison tails off, or maybe fades out – Stiles isn't in much of a position to tell the difference. All he can hear now is a strange, rising, whining sound... the same that started when Kate was shot? Where's it coming from? Is that Peter making that noise?

The volkodlak's eerie whine rises into a scream, a drawn out moan of agony that starts and then never entirely stops, breaking into tortured sobs of noise as Peter hurls himself at the door of his cell, once, twice – again and again.

"What's it doing?" Allison hisses. "Why now?"

Stiles is wondering the same thing. It makes no sense that Peter could be _unhappy_ that Kate is hurt, that she isn't going to be allowed to finish what she started... does he mean to kill her and Allison himself?

In the next cell, Lydia stands pressed up against the bars, staring first at Peter in rising horror, then at Kate, at the remnants of her circle, then at Stiles. For a long moment she locks eyes with him, and Stiles thinks, _oh god_. He'd just _watched_ Kate picking up the book, stepping into the circle, running her fingers through Derek's blood...

On the fifth blow, the door to the volkodlak's cell doesn't merely give way, it flies clean off its hinges across the room. Peter steps out into the dungeon, limping and still moaning, and turns towards them – Stiles, Derek, Allison and Kate – and howls so pitifully one might almost think that he, not they, were about to die horribly. He begins to lumber toward his prey one dragging step at a time.

" _Allison_ ," Stiles hisses, " _run_. You can – maybe still..."

"Shut _up_ , Stiles," she hisses back. Her first arrow hits him on the left breast – it should have gone clean into his heart, but Peter keeps coming. Her second lands in the centre of his forehead. The third goes through his ankle, the fourth lands in his left eye. Peter keeps coming as though he never feels a thing – maybe he doesn't, not from the body he's wearing. The dungeon rings with dull clangs as both Erica and Isaac wrestle helplessly with the doors of their own cells without success. By the time Allison drops her bow and draws her daggers, Stiles is trying to calculate just how many extra seconds of life he might be able to buy her if he can only drag himself close enough to throw himself underfoot and get Peter by the ankles the way Erica had. The odds must be one in a million that it could be enough to save her, but he already knows going to do it, because if even one of them gets to get out of this alive...

The streak from the dungeon door hits Peter at such speed that Stiles doesn't know what he's seeing. Not until he hears Allison yelling "Scott!" does it come to him that the drawn out vowels of the streak's battle-cry had included _Allison's_ name. Relief hits Stiles with deadening force – right now he'll gladly forgive Scott for waiting until the very last minute to show up – even for imagining that it's _Allison_ here that really needs rescuing, because of _course_ he would. But Scott is here and that's all Stiles knows for sure as the dungeon in front of him dissolves into a war of snarls and slashing claws.

Blindsided, the volkodlak reels under the assault, then wakes from its zombie-like stupor with an animalistic fury. But its flailing claws and teeth are poorly targeted, and Peter's latest body is riddled with arrows and coming apart at the seams. With blood running into his single working eye, with his wounded ankle buckling underneath him, Peter buries his claws in Scott's arm to no avail. Scott slashes at his throat with his free hand, again and again until the volkodlak's head hangs from a thread, and its body slumps, lifeless.

Peter had hardly stood a chance.

"Allison!" Scott is at her side almost before the volkodlak has stopped moving. He's a mess, though surely only a fraction of the blood is his own.

Stiles stares blankly at the fallen body, his own heartbeat hammering in his ears as Allison reassures her lover that she's not hurt. In a few minutes, Stiles is probably going to start resenting Scott for his priorities, considering that he's right here and it's not Allison who's actually hurt, but for now he's still riding high in far too many warm and fuzzy feelings about his werewolf-best-friend to sulk all that much. On his left, Derek has his head tilted back and his eyes closed, breathing in short, shallow pants. He's horribly pale but seems to be on top of the pain for the moment. Stiles finds himself weighing the unthinkable notion that they might have somehow made it through.

A soft, short exhale of pain tracks to movement in his peripheral vision, where Kate has dragged herself to the nearest wall, now working Allison's arrow out of her thigh. Unpleasant as Stiles may personally find the reminder that Kate too is still to be counted among the living, Allison will probably veto any attempt to make a case for her abrupt and painful death. Realistically, as long as Kate's still bleeding on her knees, even Scott will probably take more convincing than Stiles is up to just yet – no matter how many problems it'll solve.

A little startled by his own futile bloodlust, Stiles finds his earlier nausea returning in force, and does his best to make himself believe this is for the best, somehow or other. He's certainly seen enough blood already today to last him a lifetime.

Though come to that, shouldn't that leg wound of Kate's be bleeding a little more obviously?

Stiles has not quite processed the not-wholly-unaccountable fact that Kate is visibly healing when Derek jerks as if startled and opens his eyes.

"Stiles," he breathes, " _he's still here_."

"What?" says Stiles, which he would absolutely have followed up with a more intelligent question if that hadn't been the moment he realises there's one more person moving in this room than there should be. "Scott! Look out!"

Scott twists around barely fast or far enough that the dagger to his back goes through his ribs at an angle, missing his heart by inches. The rough gasp that drags out of him is unaccountably worse than any scream. His hands twitch feebly toward the source of the pain, grasping at the air without either the strength or the resolve to find the hilt and tug it free. Allison cries his name, but it takes her a horrified second to remember her own daggers, and by then, Peter in the body of the fallen hunter has an arm around Scott's neck, a second dagger pressed beneath his chin, and Allison freezes.

_Human bodies_ , Stiles thinks, uselessly, _If they're fresh, or maybe just if they're close enough..._ then it hits him just what Peter is trying to do, that he's not planning on staying in that human body at all, and it's Stiles who almost stops breathing. _Scott_...

Scott slashes blindly at the body behind him with his claws. Pain hardly seems to faze Peter anymore, but the second blade scrapes a jagged line upwards under Scott's chin and slips out of his grasp. With a breathy snarl, Peter lets go of Scott and launches himself at Allison, who has her own daggers drawn a small infinite before he gets there, but isn't wholly prepared to deal with an enemy who can take a six inch blade to the chest without flinching – let alone who'll grab the hilt and _hold it in_.

Letting go of the dagger is a mistake. Peter simply steps back, bares his teeth in a snarling grin that probably looks much better on any of the werewolf bodies he's been working with lately, and pulls Allison's dagger out of his own chest as if it had been merely sheathed at his waist.

" _The neck_ ," Scott rasps, doubled over on the floor.

"I _know_ ," Allison hisses back, voice thick with the universal frustration of someone who did honestly know that right up until the moment when it mattered unexpectedly. It might be funny if there was any real possibility she'll get that opening twice.

The fact there is a second human body lying on the floor, ready for Peter's use even if Allison does take this one down, even if Peter _doesn't_ get that one more lucky blow he needs to ensure that Scottleaks out of his own body and leaves it empty for him to take – that knowledge wraps itself around Stiles' heart like a vice. They can't kill Peter this way – not properly. They're going for the wrong target. The one they should be after... Stiles drags his eyes away from the fight to... but... wait, where's Kate?

Peter catches Allison's dagger by the blade, bare-handed. His own stolen dagger he still holds clutched in some sort of rictus-grip, even after Allison had slashed clean through the tendons on the inside of his wrist, and he raises it to strike – then freezes where he stands. Allison is still fighting to wrestle her blade out of his grip as his eyes loose focus; he's gaping now as if struck by a bolt from the blue, senseless even to the fact that Allison severs two of his fingers as she yanks the dagger out of his hand and jumps backward to put some space between them, stopping only when it dawns on her that her opponent isn't looking at her anymore.

Stiles doesn't even find Kate – on her feet, backing along the wall to god knows where – until the part where her knees and Peter's give out simultaneously. He still has no idea what just happened until Kate topples forward with a dagger in her back. Behind her, Jackson watches her fall like he's every bit as surprised by what he just did as she must have been.

Neither her nor Peter's bodies move again.

* * *

It's still not over there, and even now Stiles doesn't get the luxury of passing out until it is, but he does kind of lose track there for a while, as Allison grieves and Lydia explains and Jackson just kind of stands there staring at his hands, and then Allison gathers herself with some implausible act of human will and goes to help Scott, and Jackson goes to stand by Lydia's cell, their foreheads as close as the bars will allow.

The first part that really makes it through the fugue is when Scott appears on his knees beside him with a look of infinite concern on his face, saying, "Stiles, how bad...?"

Stiles hardly has the words for the combined effects of Kate's arrow and the hunters' nasty poison flowing in his veins, and now the excitement is over the lack of distraction is making it worse, not better – but he's fairly sure it won't actually kill him. He waves Scott away. "Help _Derek_." But when he looks to Derek, Allison is there already, one hand braced on his chest, skin to skin, as she pulls the arrow free, and Derek starts to heal at last. Stiles' vision starts to go misty again.

"Scott!" calls Isaac, "Get him over here. If you can take some of his pain, we should be able to heal him."

Scott helps Stiles to the point of the dividing line between Isaac's cell and Erica's and sits him down. Once all three of them have a hand on him, Scott wraps a hand gingerly around the arrow shaft protruding from Stiles' shoulder, and says, "Ready?"

What the arrow feels like coming out one long, awful reminder of what it had felt like going in. Stiles wants to protest that Scott's pain-sharing trick isn't working, but the veins of Scott's arm have gone thick and black, pulsing upwards in a rhythm that seems to go on and on, until the throbbing ache in Stiles' shoulder subsides into numbness, and finally into the most vicious case of pins and needles he's ever experienced as his flesh knits back together. By the time that too fades, his body has begun to feel oddly far away. He's lost track of most of his limbs, no longer sure which way is down. It's not so bad, really, as long as no-one wants him to move any time soon, which of course is exactly when he feels someone tugging him upwards onto his knees...

Any protests die when Stiles finds himself wrapped in Derek's arms, pressed against Derek's chest. Stiles' own arms are pinned at his sides, but he doesn't feel like he'd have the strength to hug Derek back properly just now anyway, so he just thinks, _oh_ , and lets Derek take his weight. (Wasn't Derek chained up a minute ago? How many minutes ago was that, really? Stiles has no idea.) It's the first time since Kate appeared from the hallway that he's really been able to believe this is over.

Scott and Lydia have hardly started to talk about who's going to go get the rest of the keys from the courtyard when Allison's father walks in through the door.

* * *

The scene Chris has walked in on looks something like this:

Allison is kneeling by the dead body of her aunt. The bodies of two more hunters and the mangled remains of one dead werewolf are lying on the floor. There's a (living) werewolf and a demon standing by the cells, one of which is empty but for a few bloody smears, the door having been forced off its hinges and thrown across the room. The remaining three cells between them contain three suspected demons and one witch. The dungeons also contain one known accomplice (Jackson), and also Stiles. Everyone not in the cells is, to some various greater or lesser degree, a bloody mess.

It's not the least incriminating scene Stiles has been a part of recently, to put it mildly.

Given these circumstances, it's perhaps understandable if Chris walks in with his crossbow loaded and a murderous look in his eyes. Realistically though, Stiles couldn't say he'd have given Mr Argent terribly good odds should this all go south a few seconds from now, which may explain why it quickly proves that no-one still living left in the dungeons is in much of a mood to mince their words when the shouting begins

* * *

"...because we did not _kill_ your guards, _that_ did," Lydia argues, jerking her chin at the volkodlak's last unfortunate werewolf body, still cooling on the floor. "And we wouldn't have had to kill your sister if _she_ hadn't interrupted us in the middle of the very ritual that wouldhave let us banish it properly, and made _herself_ the lynch-pin anchoring that thing to this plane. I'm very sorry, _Mister_ Argent, but if your people don't have the common sense not to go carrying enchanted magic books over mystical sigils then smearing demon blood all over their hands, I frankly don't have much sympathy."

Chris' eyes flit only briefly over the body of the dead werewolf. He hasn't looked back at Kate's since he walked in. Whatever brief sympathy Stiles might have felt for him in that first flash of regret, there and gone on the man's face – almost as if he hadn't even been surprised – lasted roughly as long as it took for him to start talking. "And I should believe you because?" Chris says.

"She's telling the truth, Dad," says Allison, still kneeling by her dead aunt. She sounds roughly as worn out as Stiles feels, which is no meagre statement. "It's the same creature that came at us outside and split us up. The same one that killed Harris, and Rebecca – we've been trying to figure out where it came from for over a month. Scott and Stiles have been trying to warn you about it all night."

Features hardened with thinly contained fury, Chris is not so easily swayed. "You too, Allison? You'd side with your aunt's murderers over your own flesh and blood?"

"I tried to talk her down before it got that far," Allison pleads. "She wouldn't let me. You don't want to know what she was doing when I got here."

"Are you forgetting," snarls Chris, "that the person you're defending has been hiding _illicit magical texts_ from us for years, that she consorts openly with demons – and is clearly responsible for the very same demon she sacrificed Kate's life to, to fix her own mistake-"

This is where Stiles – still woozy from pain and the after-effects of demonic healing, barely holding himself up on his knees, and coming off what already feels like the longest day of his short life – officially snaps. "Oh my god, can we for once _stop_ coming at this from where everyone assumes the worst possible motivations from everyone else? You _know_ there are incubi and succubi out there that don't kill people! Some of you even used to be okay with that! You used to have treaties with werewolves, for god's sake! Did you ever give Allison a good answer for why you don't do that anymore?"

"They pose," Chris pronounces, "A _danger_. One we-"

"So does _not_ having them around! Do I need to point this out to you? You know, the mad paranoia over keeping the truth about binding incubi secret – that all makes so much more sense when you find out it's so easy to do it can literally happen by accident – though I suppose you maybe lose that kind of perspective once you've made it so taboo no-one remembers the _why_ anymore. But you know what else? The only reason Lydia had been using that book at all was so we could find a way to _break_ that binding after it happened! And we did! That's been completely possible all this time, only no-one _knew_ because you were all too busy trying to bury that knowledge to do anything with it!"

The slightly overlong pause before Chris responds is more or less the only sign he's noticed any revelatory details in this version of events. "If I were you, Stiles, that's more than I'd admit so lightly," he says, voice low and dangerous in a way that only makes Stiles want to roll his eyes. "And even if I believe you," he goes on, "I suppose next you'll want me to believe that this parade of demons eager to press themselves into Lydia's service showed up by no more than coincidence."

"Oh, they don't take their summons from me," says Lydia. "Not except inasmuch as I can dock these three's pay, and if they don't like it they're free to go as they please. I didn't even know they were demons until after we all got home. As far as I understand it, they're only here at all so they could keep an eye on Stiles and Derek. Shocking how even demons can manage to look out for their own."

"Still not a demon, if anyone cares," grumbles Boyd, to the great interest of basically no-one.

"You want to hear the real reason that first incubus ever came here?" says Stiles, before Chris can get a word in edgeways. "Because Lydia's mother bound him to something here to save his life after a hunter betrayed him – a hunter who decided to forget the rules, he was going to _keep_ one of those books he was supposed to destroy – and I'm not even going to speculate why, I think we can all guess that one easily. But then some _other_ hunters went and woke that incubus up prematurely when they murdered the succubus he'd raised like his own daughter while she came to check on him. Oh, and for the record, _that's_ what happened to that clan who went missing back in winter, if you were still wondering. Only when _he_ flies back here in a mad rage, you and the rest of yours have chased Lydia's mother away, so there goes the one person here who would've known what to do with him! Come on, did you ever really believe _I_ killed that first incubus? The only reason we survived that night alive was because _Derek_ here tracked him to the Tower and took him down before he could draw any more attention – only even that didn't work, because _none_ of us knew that first one was bound here, or that he could start running around wearing all those _dead werewolves_ you leave lying around, and killing all those people you just kept on blaming on Derek, even when none of them even _died the right way_!"

Not until Scott's brow begins to furrow in a fairly serious fashion does Stiles remember how much of this long story would be news to him – hell, half of it was news to Stiles himself this time yesterday. Or maybe trying to summarise the whole thing in the space of three breaths was a bit much to expect other people to follow. Well, whatever. He doesn't honestly give a much of a damn whether Chris is keeping up with every detail – he's going to hear this whether he likes it or not.

"Your rules, your system, it doesn't _work_ , don't you get it? It just ends in tears over and over, and people on both sides bleeding out all over the floor." Stiles takes a breath. "Is it so much to ask that we all stop hiding things from each other and killing each other for just long enough to try something else for a change?" he pleads.

Chris' jaw works soundlessly as he processes this spiel. Or perhaps just as formulates a suitably cutting reply. "You should have taken your ideas to Kate," he suggests, in acid tones. "She was the one who had all the enthusiasm for finding _alternatives_ to tradition."

"Kate never wanted to work with them. She wanted to _use_ them," says Allison. "I went to her for help because I thought she was the only one who would listen. But she was never really listening. She heard what she wanted to hear."

"Maybe Kate was the one with a point you've missed," says Chris. "Her only compelling argument for why I should take the chance on trusting Scott was in the name of his aid for the greater good. If not for your influence-"

" _My_ influence?" Allison snaps, seeming to have reached some limit of her own. "He's not an animal! Is that so hard to see?"

Chris gives Scott's hairy beta form, in the shredded, bloody remains of his clothing, a long look, studiously unmoved. Allison looks away.

"Fine. _Fine_ ," she says, and looks to Scott. "Scott, if we can't talk my father around, I think we both know there's only one way we're all going to get out of this. You're going to have to kill him for me."

"What? No!" Scott protests, eyes wide with betrayal, even as Chris straightens and tenses. "Allison!"

Chris is still putting together what just happened when Allison wheels back on him, triumphant. "You see? Whatever Kate said, I don't 'control' Scott – I never have. He controls _himself_."

Chris breathes out, long and angry. "A wolf is one thing, but would you tell me these _demons_ are to be trusted?"

"Why not?" snaps Stiles. "They literally cannot break any vow they make to you without dying in excruciating pain! Is the idea to make _sure_ the only hunters who even try to work with them are the ones who want that power themselves, like you were only just warning me about earlier? Because that's where it goes!"

"I don't like what you're implying about my own kin," says Chris.

"She was trying to bind Derek to her, Dad," says Allison, and Stiles isn't sure exactly when she passed the point of trying to talk around that detail, only that it may have been a while ago. "She didn't even bother to deny it when I got here. You can't reason that away."

Chris at last has the decency to be properly lost for words for several moments. How much he's really surprised Stiles can only guess; Chris keeps any of that close to his chest. "Can I talk around wilful defiance of our own most fundamental laws? No. I wouldn't even try. But what exactly do you expect me to do, if not treat every one of you who've been party to this by the same rules?"

"You don't have to do _anything_!" says Stiles. "Just let us go on the way we have been! Forget that Scott and Boyd and the rest aren't human, let Lydia keep her books, and maybe next time some angry demon shows up with a score to settle, we can find a way to deal with it without all lying to each other and working at cross-purposes every step of the way! How much harm can that do?"

There's nothing kind in the look Chris turns on Stiles. "So your solution is that I turn a blind eye?"

"No," Derek rumbles, speaking up for the first time since Chris walked in, "you're also going to swear to me you'll keep our secret, and take no action to harm or remove any of us from this place, as long as we choose to stay. In return, _I_ won't rip your throat out where you stand."

Not that Stiles will ever not enjoy hearing Derek violently threaten people he doesn't like, but this strikes him as a possibly counter-productive tack to take. "Derek," he hisses, "remember what I said before about not aggravating the-"

"The brother of the hunter who shot me, clapped me in chains, threatened your life and tried to bind me against my will?" snaps Derek. "I'll say to him what I like."

"I don't makethe rules I uphold," says Chris, anger rising, not even addressing Derek. "But do I have to remind you, those laws exist to protect _our_ kind, _not_ his? What Kate might have seen fit to do to a demon-"

"She wouldn't do to a human?" asks Jackson, incredulous.

Stiles blinks at him. He'd honestly mostly forgotten Jackson was there. Since recovering from that blow to head and somehow staggering to his feet long enough to stab the perpetrator in the back, Jackson has been violently sick in the corner, and ever since has clearly been holding himself up his own stubborn pride alone. There's a deranged look in his eyes even now; he's probably still seeing two of everyone. "Is that what you're saying, that maybe Kate would _rape_ a demon, but at least she wouldn't do that to a human? Oh, I'm sorry, should I be hedging my words a little more? Call it 'binding', or whatever other sick excuse she'd use? Because if that's what you're saying, _Jesus_ , do I have a story for you."

"Jackson..." whispers Lydia. She reaches for him from between the bars, but he shakes her away.

"What," Jackson rambles on, "so she gets to turn _me_ down in front of everyone the moment I start taking what we did for granted – but the moment _I_ say no next time she corners me, my opinion doesn't matter? So go on," he spits, "tell me I deserved it. Tell me I needed to be put in my place. Tell me I must have liked it, 'cause god knows I always did _before_. At least the monster that came after Lydia would've made her _enjoy_ it; wouldn't have made her see him every _fucking_ day for the rest of..." Jackson shakes himself. "So she's dead. And yeah, I did it. Don't you _dare_ ask me to say it was less than she deserved."

Stiles stares at Jackson, open-mouthed. He hadn't... _Jesus_. He remembers that morning, when Kate had laughed and turned Jackson away with all the Tower to watch. He remembers laughing too.

Had Lydia known? A look in her eyes says yes, but a look at anyone else in the room shows only mirrors of Stiles' own shock. Yesterday he might not have believed a word of it – now, he almost doesn't know how he ever believed anything else.

"He's telling the truth," Scott breathes, like he can't quite believe it himself.

Chris finds every pair of eyes in the room turned on him. "If that..." he starts, but trails off. He looks like he badly wants somewhere to sit down.

"You've made your point," he says at last. "I won't defend my sister against whatever she may have done. But I need to consider this."

" _You_ need to consider whether you have any other alternative left where your daughter ever speaks to you again," says Lydia. There's nothing light left in her tone.

Sighing, Chris looks down, brow furrowed in thought. He looks sideways at Stiles, frown deepening.

"You really bound yourself to an incubus by accident?" Chris asks, as if now he's the one grasping for a distraction. Jackson scoffs out loud and sits down heavily on the floor.

Stiles feels suddenly very self-conscious. "Did I say that was _me_?" The look on Derek's face suggests he had. He's starting to feel too light-headed to be expected to continue this conversation. "Well. It was kind of a little more complicated than that..."

"The fault was mine," says Derek. "I was careless. But he unbound me deliberately, though I'd promised him it was impossible." Glaring daggers at Chris, he finishes, "Had I known what your sister would attempt, I would never have let him."

He doesn't actually add, _and I mean to do fix that oversight_ – which is probably for the best, though Stiles hears it in every word. Maybe they can talk about how to break that part to Chris a little more gently, later.

Because there'll _be_ a later. Whatever they all had to go through to get it – and it might be days before Stiles can even begin properly think about that part – somehow, they've won this. They all get to stay.

"Should I... go get the keys now?" asks Scott, looking uncertainly around the room, and that really seems to be the end of it.

* * *

Stiles is not surprised that Derek insists on taking him up to bed while the rest of the household are finally freed from their cells, while Allison and Chris postpone whatever stage of the argument comes next in order to deal with four dead bodies – three of them members of their own crew. But it's not until Derek's helping him out of his bloodstained clothes and into something cleaner that it becomes apparent that he actually _means_ 'taking him to bed' in the sense of 'and lying down and going to sleep, without other diversions'.

"Don't you want to...?" Stiles asks, puzzled. Not that he's entirely in the mood. Actually, while half of him is flushed with the joy of victory and wants to celebrate right away, in the filthiest way possible, the rest of him is just about asleep on his feet.

"Do you?" asks Derek.

"I could do?" He could certainly _try_ to be. By his own estimation, it's been at least a week since he and Derek last had sex, and given that he's pretty sure Derek never did follow up on that suggestion that he take the time to sleep with someone else while they spent their week apart – given the arrow and the poison and everything Stiles knows about how this works for his kind – he'd been imagining Derek must be pretty much hanging by a thread at this stage.

"But you'd probably fall asleep in the middle of it," says Derek, pushing Stiles gently down on his bed. The scenario alone is enough to awaken a vague whisper of interest in Stiles' lower regions, more or less by habit alone, but Stiles has to admit Derek has a point. Pre-dawn light is already starting to leak in from outside, and the fact Stiles hasn't slept a wink all night is starting to catch up with him.

"I just meant, if you needed to..." he offers anyway.

Derek kisses him, slow and languid, though without any real heat to it. Then he climbs into bed with Stiles and presses himself to Stiles' back, his bare hands creeping under Stiles' shirt to flatten against his chest – not unlike what he'd done out by the bonfire the night after the fair, what seems like an age ago. "This is fine," he says.

It occurs to Stiles that Derek may be just as tired as he is, though he's always been a little hazy on just how much sleep Derek needs, if any. Possibly now is not the time to ask.

"We can make up for lost time later," Derek promises, "Tomorrow, once you're rested – then we can see about undoing that spell of yours properly. And I do intend to."

Stiles feels his heartbeat pick up under Derek's hands. That Derek wants the binding between them renewed – or at least sees it as an acceptable side-effect of all the sex he wants to have – isn't news, but this is the first he's said so much out loud. Even now, Stiles isn't entirely clear on how much Derek's raising it as the goal and how much it's functioning as euphemism. The distinction seems potentially significant. "Soooo... you're still sure you do want to..."

"The best thing about having that binding back in effect is going to be not having to deal with that question anymore," Derek says bluntly.

If Stiles were more awake, he might possibly have been able to come up with a better answer for that jibe than, "You know Chris Argent isn't going to like that."

"Good," says Derek, "because I plan on being as obvious as possible about exactly what I had to do to make it happen."

Were Stiles more awake, he might have felt a little more scandalised by that one. But since he's not, the general feeling that he could be pretty okay with Derek's plan is the last clear thought he'll remember having before drifting off to sleep.


	18. Epilogue

They don't actually have sex when Stiles wakes up, mostly because Stiles, having not eaten in a long, full and stressful day, wakes up hungry. Not so hungry that waking up with Derek in easy reach isn't tempting, mind – Stiles has probably never been _that_ hungry in his life – but it has been something like a full twenty four hours since he last ate. Being properly rested, if anything, only makes him that much more aware of how many meals he's missed.

The pressing need to lie in bed forever and ignore all bodily demands indefinitely wars with both impulses. Nonetheless, Stiles will still swear blind that that's not actually what he's suggesting when he rolls toward Derek and says, "We don't have to get up right away if you don't..." before then his stomach rumbles, loudly.

Derek looks down at his stomach skeptically, then back up at Stiles again and shepherds him toward the kitchen in search of food in a way that would probably be patronising if he wasn't getting the inkling that Derek's interest in making sure he's well rested and fed has ulterior motives. Motives Stiles will be entirely on board with about one meal from now. 

In the main hall, Erica and Isaac are already seated at one of the tables with the remnants of a couple of loaves of bread and a pot of stew. Stiles is not so hungry that the fact they've both got their wings out doesn't give him pause, but he still has both feet over the bench and a chunk of bread in his mouth before he gets as far as asking, "Did you go down to the kitchen like that?"

Erica quirks an eyebrow at him. "Someone had to tell the cook _something_ about what happened last night. Boyd talked to her while you were out."

"And?" asks Stiles, muffled around his second mouthful.

Isaac shrugs. "She asked if demons were going to expect larger servings, gave us the pot and chased us out."

Stiles swallows with only moderate difficulty. Well, that sure adds a lot of weight to his old suspicions that the cook has known perfectly well she's been feeding at least one werewolf for months. Stopping now to think properly about just how _much_ of his life has turned upside-down in the last twenty four hours is probably only going to be a shortcut to severe indigestion. Probably best to postpone that particular crisis for some later time. 

"We were just on our way out anyway," says Isaac. "Flying into town for the evening."

Evening? Stiles looks out the window. It's later than he'd realised – he must have slept longer than he'd thought.

"You know – see who's around the travellers' inn," Isaac goes on. "See how much of yesterday we can work out of our systems. I assume _you're_ staying in." This last is directed at Derek.

Stiles would invite Isaac to take his speculations elsewhere, but it probably stands to reason that making sure Derek's got plans on that front is more or less what amounts to mother henning when (almost) all your friends are sex demons. Come to that, in the middling light of afternoon, even Isaac and Erica's kind offer to heal him has come to look suspiciously like it may have been less _for_ him than it was about anticipating Derek's predictable need to get his hands on Stiles as soon as possible without being awash in second-hand pain. Not that Stiles would particularly hold it against them if it was – the absence of agonising pain is its own reward. Anyone who'd think it ought to take some of the fun out of it, knowing that sex is as fundamentally necessary as eating and sleeping his to Derek and his kin really had no idea at all.

"Speaking of yesterday," says Erica, significantly, "I was thinking..."

The fact she's talking to him becomes apparent to Stiles slightly too late for him to realise he should probably worry about what's coming.

"That rule about no sex with anyone in the Tower," Erica continues, "Isn't that a little unnecessary now there's nothing left for us to give away? Maybe we could renegotiate."

Stiles swallows as quickly as he can manage without choking. "Oh my god, it hasn't even been a _day_! I am not having this conversation with you over breakfast."

"Dinner," says Isaac.

" _Or_ dinner. Don't you have innocent people to seduce? Somewhere that's not here?"

"Later, Erica," suggests Derek, firmly.

Erica exchanges a glance with Isaac, but only shrugs at Stiles and Derek, not looking much discouraged.

"Have fun without us," says Isaac, and they both head for the door.

Stiles stares at the ceiling. "I don't know how you kept them away from the hunters for so long," he says, to Derek.

Derek only smiles back. "Speaking of things the hunters wouldn't approve of..." he says, and takes a slow bite out of his own loaf.

Stiles finishes his stew fairly quickly after that.

By the time they make it back to his quarters, however, Stiles is awake enough for his mind to have started working. Awake enough to have remembered one of his earlier ideas regarding what they're about to do – something that occurred to him back when he'd assumed Derek was only going to maybe wander around for his prescribed week of unbinding before making it back with minimal drama (yeah, ha ha ha). Really, the fact Stiles manages to remember the thought at all after all that's happened since feels like far too much achievement to waste.

"Hey, before we do this," he says, jogging a few steps into the room in a slightly exaggerated rush, putting a couple of paces between them and preserving what will be probably his last chance to get a few words before being terminally distracted, "I did have this one idea..."

Derek watches this dance with an expression of mild bemusement and no small interest. "Yes?"

Stiles takes a breath. "Do you think you could put me under your thrall right now?"

Whatever Derek might have been expecting, this was obviously not it. "This again? Really?" Derek shakes his head, huffing lightly. "You are incorrigible."

"I just want to see if it works. We're not going to get another chance like this." Never let it be said Stiles isn't dedicated to the cause of knowledge. "With the binding broken, it's possible, right?"

"I think I'm going to have to be insulted if you imagine I've left you with any virginity to work with, after all this time," says Derek, advancing on Stiles now in a fairly intent sort of way. "Besides-"

Stiles skips hurriedly backward around the bed. "I'm just saying: if it resets things for you, how do we know it doesn't reset things for me as well?"

" _Besides_ ," Derek repeats, "even if I could make it work, what am I supposed to enthral you into doing? What's my leverage? You want to have sex with me _already_." He stops, frowning a little.

"I could play hard to get?"

Derek rolls his eyes. "Because there's nothing I enjoy more than watching people pretend not to want me to make some sort of point." He fixes Stiles with a look.

Stiles tries not to wring his hands, suddenly nervous. "Look, if it doesn't work, it doesn't work, but this could be our one chance to find out! Aren't you even a little curious?"

"Not particularly. You've always been more than curious enough for both of us."

"Can't you just give it a try? For me?"

"It doesn't work that..." Derek starts then sighs through his nose, exasperated. "Maybe this was a mistake."

"What was?" asks Stiles, stupidly.

" _This_ ," says Derek, unhelpfully, as if the very space between them is at fault.

"You mean... having sex with me? When has _that_ ever been a mistake?" asks Stiles, realising a little too late what he's said.

It's some small mercy that Derek doesn't give that one the answer it probably deserves. Stiles can't say he's particularly feeling that mercy, though, when what Derek says instead is, "You gave me the chance to think this over before rushing back into it again. Maybe I should've taken it."

The rather horrible possibility that Derek is serious hovers over Stiles like a storm cloud. "But I thought... isn't this a bit more urgent than that?"

Derek shrugs and looks away. He's still frowning. There's nothing playful in it anymore. "Doesn't mean it has to be you. The nearest town is only minutes away by air. Erica and Isaac are already headed that way."

Stiles gapes at him, unbelieving. "But last night you said..."

"Last night I was tired enough not to think beyond the easy option," says Derek. "This is now."

"Does this mean you're... not coming back?" Stiles feels like he's having a bad dream. He can't be hearing this – Derek can't leave, not _now_ – not after letting Stiles believe it was all going to be okay. He can't have messed this up so much, so quickly – this isn't _fair_. He'd steeled himself for the possibility of losing Derek back when he'd worked the spell to break the bond. He'd been ready for the worst when Derek had learned about Peter; been all but resigned to it after the cascade of disaster after disaster that had followed. He'd been _so sure_ Derek was going to leave for good when he'd voiced the question in Lydia's room last night – then, the threat of never seeing Derek again had loomed so large that it was more than he could bear to let himself imagine otherwise. Just last night he'd asked again, just in case – though if he's honest, by then it was already becoming the kind of meaningless pleasantry you offer _because_ you know they're going to turn it down.

Today, in his own quarters with the late afternoon light already losing its glow when he's barely been awake half an hour, losing Derek is supposed to be impossible. It doesn't matter that the right thing to do is to give Derek the space Stiles promised him the last time they had this conversation – had urged him to take, even. It doesn't matter that Derek hasn't _said_ ,'I'm gone for good', or that Stiles doesn't know for sure he won't change his mind again in a few hours. Only now does it come to him that getting to believe he had Derek back only to lose him again like this could be so much worse than losing him when Stiles had still been mostly-expecting it. Maybe worse than never having had him at all, which is a fate Stiles can't even contemplate.

They've been through _so much_ , and knowing he'd get to have Derek again at the end of it was the only bright spot, the one good thing that got him through. That they might notget to help each other through this step is just so _wrong_. It's been a whole week since they even really touched, and Stiles hadn't _known_. He hadn't realised then it could be the last time – that tomorrow would be the day Lydia threw the book at him and told him to do it now or never, that he'd never have that chance to properly say goodbye. The memory of that last time sticks in his throat – the press of Derek's legs wrapped around him as he moved, pulling their foreheads together and kissing him until Stiles couldn't concentrate on that anymore, leaving them breathing the same air right to the end. The idea of never touching Derek again turns Stiles' gut to ice. Derek can't mean... he just _can't_. If he lets Derek walk away now... he can'tlet Derek walk away.

"Wait!" he cries. "Don't – you don't have to!"

"Stiles," Derek warns. He stops short of the door, but he doesn't turn back again.

"Just – stay, please? You don't have to do the thrall. Forget about it, I won't even mention it again. It doesn't matter. Stupid idea anyway."

For a long moment, Derek doesn't move. "You're going to behave?"

"Yes! No more stupid questions, I promise. I won't even... I'll just stop talking now." If Derek believes this, he'll believe anything; Stiles is grasping at straws.

Derek sighs, visibly. "Alright, Stiles. One chance." He strides to the bed, not even looking at Stiles as he does it. Turns, without even really stopping, and slouches back to sit on the edge, knees spread. "Convince me."

Stiles is moving almost before he's processed what Derek's asking for. It's obvious in every inch of his posture – and it isn't, because they just don't _do_ this that much, at least this way around. Not that Stiles has any real objection to sucking Derek off, but when the link between them only goes one way it just seems like a waste to spend his energy when Derek could do the same to him _and_ for himself at the same time by proxy. All Stiles knows for sure is that by the time his knees hit the floor, being given the chance to bring Derek off entirely by his own devices feels enormous, like a gift he doesn't deserve.

The butterflies zooming around in his stomach aren't just excitement; the pressure is on for Stiles to make this good. Derek's only half-hard yet, which is unusual enough for how this sort of thing usually goes. Something about that makes it more intimate rather than less; it can't be everyone who gets to see him this way. It shouldn't be anyone else ever again. That's what Derek wanted, right?

In the back of his mind, something about all this nags at him – something he's missed, in the overwhelming rush to keep Derek here. It's hard to concentrate on that weak impression that he's missing something important, but...

 _Oh_ , thinks Stiles, as it clicks in his head a way he'll probably care about later, when he's not staring Derek's cock in the eye and feeling every minute of the week he's gone without. He pushes the thought away again. Licks his lips.

Should he use his hands first? That seems like cheating somehow... and now he's definitely overthinking how to begin. He's pretty sure now is not the time to ask for tips on how to do this right. Stiles braces his right hand on Derek's inner thigh, his left on the edge of the bed, takes a breath and opens his mouth over the head of Derek's cock. Derek makes a noise like a sigh – faint, but pleased. Encouraged, Stiles begins exploring with his tongue with a little more boldly – the line of the slit, the pull of the foreskin beneath the head – and is rewarded by Derek starting to harden against his palate. The taste of Derek's skin down there is different in a way he doesn't know how to describe – satiny in texture, and Stiles can't get enough of it. His mouth isn't large enough to take Derek all the way to the base, though maybe if he tried taking it down his throat the way Derek does for him sometimes...

"Careful, Stiles," Derek warns. "I'm not going to suppress your body's reaction for you if you bite off more than you can chew."

...or not. Okay then. Not that he's not tempted to try, just out of spite, but even he's capable of taking the hint. Instead, Stiles tries hollowing his cheeks, bobbing his head a little – things that he knows worked when Derek's done this for him, but hasn't really tried – Derek's always been more active when they've done this before. It's difficult to really concentrate though, to pay as much attention to the signals that will tell him if he's doing this right as he should, but the truth is that Stiles isn't really aware of much of anything but the heady pleasure of _Derek_ there in his mouth. Until suddenly Derek is grasping at the back of his head (just on his hairline, two fingers falling on bare skin below, curled over the curve of Stiles' neck), as Derek tenses, and groans, and comes in his mouth and comes and comes.

Stiles pulls off, a little dizzy, mouth full to leaking and the rich, salty taste of Derek's semen coating his tongue. Knowing he just made Derek come all on his own, without hardly a thrust from Derek or a whisper of his own second-hand pleasure under Derek's hands, is thrilling and licentious in a way that makes him wonder how they haven't done this before. That must mean he's done well, right? Suddenly nervous again, remembering that might have been his only chance, he looks up, seeking reassurance, honestly unsure what comes next.

Derek's eyes have gone dark, heavy-lidded with lazy satisfaction. Leaning backwards, he crooks a finger at Stiles, beckoning.

The butterflies in Stiles' stomach burst into sparks as he climbs eagerly up over Derek, following him down until the back of Derek's head hits the mattress. With one of Derek's hands on the back of his head, Stiles finds himself pulled down into a bruising kiss, Derek's tongue sweeping the corners of his mouth. He's quite breathless by the time Derek lets him go.

"Clothes," says Derek and helps him out of his tunic and pants. Derek reclines on his elbows as Stiles climbs back over to straddle his hips, eyes dropping significantly to Stiles' now even more obvious erection. "You enjoyed that."

"Well, yeah." This comes out more breathless than it had sounded in Stiles' head. The slow rub of Derek's thumb down his inner thigh is horribly distracting. "What do you wanna do now?"

Derek's eyes flick upwards, considering. He nudges Stiles gently backwards – just a little, so that his own erection (not even faltering after that first orgasm) presses into the crease of Stiles arse. Stiles feels his mouth go a little dry.

"Like this?" he asks. Suddenly there's nothing he wants to do more. Stiles pushes back, feeling the hard length rub between his cheeks.

"See what you can do for me this way." Derek settles himself. Evidently, he wants Stiles to do the work again – maybe he's still not quite 'convinced' – but any nerves Stiles might have suffered this time are well and truly subsumed under the swell of lust.

He has to make himself notlook at Derek while he lines himself up, though it feels like the easiest thing in the world to press himself backwards until Derek's erection is pressing into him, slick and firm. God, this feels _right_. Has it really been hardly a week since they did this last? It feels like forever.

Stiles looks up, looks Derek in the eye almost by accident. Derek quirks an eyebrow at him.

"Whenever you're ready," he says, though there's a husky edge to it that undermines the attempt at ambivalence, and Stiles couldn't look away now if he wanted to, Derek's holding his gaze as though he couldn't either. Stiles braces himself on his hands and knees and starts to move.

At the back of his mind is the awareness that his performance matters, that he needs to make this good for Derek, but it's hard to focus when it feels so good – when he almost can't get Derek back inside him on every stroke fast enough. His own erection all but throbs, he's so hard – normally by now he'd have Derek's helping him along with his hands, though when Stiles reaches blindly for himself now Derek bats him away – "Not yet," – Stiles supposes he can't really blame him if he wants this to last. He feels like he could come untouched, any moment.

But it's Derek who starts to come first, for the second time – holding Stiles down by the hips in a clutching grasp, making him stay still and just _feel_ as Derek pulses and shakes deep inside him, for what seems like an implausibly long time. They're both panting by the time Derek stills, and Stiles almost can't believe he hasn't come too – he feels like he must be harder than he ever has been before in his life.

Derek growls his name, or hums it – Stiles isn't even sure how to describe the way it sounds – and slides a hand up from his hip, along his back to the back of his neck while Derek leans up into his space and kisses him again, hungrily. Then and only then does he move his hand to Stiles' cock, still holding him steady by the hip, his own cock still pressed deep inside Stiles' body as Derek works him tantalisingly slow. It seems to go on for a small eternity before Stiles finally comes in his hand, in long white streaks that land on Derek's chest. The world whites out, and Stiles loses some time.

They're still where they were when Stiles picks up the thread again – Derek underneath him, Stiles clutching at him and dizzy with euphoria, but not for long. Derek growls, " _Stiles_ ," in a voice like he's making a claim, and rolls them over until Stiles' back hits the mattress. With Stiles' come still drying on his skin, Derek fucks him one more time in a furious rush. He comes deep inside Stiles for the third time, and only then at last pulls out and collapses next to him – around him, holding him as Stiles clutches back, and wonders through a haze of exhaustion what he ever did to deserve anything that felt so good as this.

* * *

"That," says Stiles, after, "was _intense_."

Derek rolls onto his side and props his head on an elbow, observing Stiles with a sly look. "You did ask."

"Yeah," agrees Stiles, who is not even close to regretting it yet. Not that it wasn't unnerving – in a way that's probably only going to get stronger once he's far enough from the moment to process it properly – but not in a _bad_ way, exactly. More eye-opening, if he had to pick a word. "People last a week like that? I don't think I could've gone an _hour_."

"I don't think I could have drawn it out that far anyway," admits Derek. "I haven't tried pushing it nearly that long. Never saw much point."

"If you're not really into toying with your prey... yeah, I get that."

"Well, if I'm honest, I was a _little_ curious whether I could get it to work too," says Derek, making the admission flirty enough that there's no way he didn't choose that wording deliberately, and if Stiles had ever doubted before that he's more than a little bit in love with the guy – _demon_ – really, who _cares_? – next to him, it just evaporated. Maybe he should mention that sometime, he thinks, dizzily.

Or maybe he should just wait until Derek can feel that for himself, just because Stiles wants him to know. That seems right, somehow.

"Sooo..." says Stiles, running a toe up the inside of Derek's calf, "are you thinking what I'm thinking yet? Or..."

"That only counted as once," says Derek, rolling back into Stiles' space, so he can mouth Stiles' shoulder in between saying, "Now, the _next_ time – the one after that – _that's_ what will really count."

Stiles must be giddier than even he realises, because it comes out aloud when he thinks, "Hey, maybe six months from now, we could unbind you again – see if the thrall still works then..."

Derek pulls back a bit and looks at him. "I think there's going to be a limit to how many times even I can convince you I'm thinking about leaving," he says, though he already looks a bit like he's seriously thinking about it – or maybe even about other ways to make it work, which is all Stiles could really have asked for.

"Seriously though, we need a complete new theory on magical virginity. For starters-"

"You can talk to Lydia about it later," says Derek, then captures his mouth and pulls Stiles between his legs in a way that implies he meant _much_ later indeed.

Stiles can find no good reason to disagree whatsoever.

**Notes for the Chapter:**

> Thank you all for reading (especially those of you who've been here long enough to have had to wait through some of the longer breaks in updates). Feedback much appreciated in any form.


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